Navistar/IH MaxxForce 7 (6.4L Powerstroke) experience/opinions?

[d24tdi]

For passenger cars and also for the heavy equipment I operate for work, I have kept a hard rule up until this point of staying away from any post-2006 diesel equipment with aftertreatment systems. Especially those engines that are notorious for trouble.

However, I recently had a vocational truck come available to me that was such a good deal that it didn't make sense not to buy it. It is a 2017 International TerraStar (small medium duty truck comparable in size to a Ford F-550) with the infamous MaxxForce 7 engine. This engine is a close relative of the 6.4L Powerstroke used by Ford from 08-10. It has a terrible reputation in the Fords and equally bad in what I am able to read and hear from heavy truck owners.

I bought this truck knowing I might need to abandon the engine and chassis and transfer the vocational equipment installed on it to a different platform. I got it cheap enough that I can do that and still be looking good in terms of value, so that is the default plan (likely would find a clean older IH 4300 chassis with DT466E since that is what we run in most of our other trucks of this size and they have been great).

However::::::: this TerraStar with the MF7 actually fires right up and runs well. Engine has a Navistar factory reman tag on it, so it's had a motor already at some point, no idea when, but not too surprising given the known extreme short lifespan of this engine. 160k miles on the whole truck, which is a lot for the MF motor hence the replacement I assume, but no challenge for the Allison trans or other components, so probably plenty of life left in the rest of it. California truck, cab is clean, body is good, the PTO system works well, interior functions are all working, glass and rubber are even good. Transmission works well and the whole setup is pretty nice. It would need some rear brake work to hit the road, but that is standard cheap Ford F-series parts so no big deal there.

The engine starts easy, and runs nice and smooth. So now I am of course tempted to explore the question: is there still some life to be gotten out of this truck as-is?

It is missing the DPF -- DP sensor tubes and temp sensors are hanging there so it looks like one could be reinstalled, but they are $$$ and known troublesome, no doubt there is a good reason it's off of there now. I understand that there are alternatives out there to reinstalling it (even today, confirmed it). Those alternatives are expensive but not too much more than the cost of a new DPF, and would stop EGR operation as well. One way or the other I would have to put a few grand in to go one of those two directions right off the bat, since for now it has codes and derates of course with the missing aftertreatment. Luckily or unluckily this engine was part of Navistar's failed attempt to meet EPA2010 regs without SCR ("Advanced EGR" ), so it has none of those items to deal with. With EGR disabled and DPF eliminated it would be a "fairly simple" configuration -- although still HPCR injection with a high pressure pump that is known troublesome, etc....

SO -- in case there is anyone here who has some firsthand feel for this engine and can give some input -- here is the key question I have at this point. If I go ahead with emissions defeat on this engine, what kind of reliability and life can I reasonably expect from it? Can they last for a reasonable lifespan and be depended on?

The three paths I have right now are as follows.
1) Put in the necessary work to get the truck on the road w/o EGR or aftertreatment as-is, and then run it for whatever life I can get from it, hopefully for a number of years and miles.
2) Remove vocational equipment from this chassis and swap to another chassis, then scrap this chassis even though it seems to run pretty good.
3) Swap a different engine into the TerraStar chassis (Cummins fits, probably could figure out some options with a T444E or some kind of gasser as well).

If it is feasible then I would be tempted by #1, knowing that the other two options would still be possible down the road if the MF7 had a major failure. But maybe someone will tell me that it makes no sense to even put a dime into this engine, and get rid of it while I can. It may have value as a running used engine.

Appreciate any thoughts from those who know this motor. TIA!

 

[oilhammer]

I am no expert, but a few of the deleted 6.4L Fords I know of have been flawless. One has over 500k miles pulling a [large] race car trailer back and forth all over the country. It's ALWAYS hooked up except for PM, so pretty much all the miles are worked. And it idles sometimes for hours and hours (it has the ambulance-vocational style high idle option, with the dual alternators).

I think these, just like the CR TDIs, can trace 99% of their "notorious problems" directly to something with the emissions control bits. Same for the much-hated 6.0L before it.

Funny that the engine in question is a Navistar engine, not a Ford engine, but Navistar decided to use a Ford oil fill cap on their engine in their truck. LOL... strange....

It sucks they had the issues with these that they did, as well as the later big inlines. Our DT466 was a beast, 100% trouble free.. old inline Bosch pump, no electronics. Always started, always ran great, and never had any visible smoke in its stack and hardly ever any noticeable smell (and its 7sp manual gearbox still worked great!).

Now I see gas V8 schoolbuses running around laboring to pull themselves, and with smoke puffs in the exhaust and cracked leaking manifolds.

 

[d24tdi]

I am no expert, but a few of the deleted 6.4L Fords I know of have been flawless. One has over 500k miles pulling a [large] race car trailer back and forth all over the country. It's ALWAYS hooked up except for PM, so pretty much all the miles are worked. And it idles sometimes for hours and hours (it has the ambulance-vocational style high idle option, with the dual alternators).

I think these, just like the CR TDIs, can trace 99% of their "notorious problems" directly to something with the emissions control bits. Same for the much-hated 6.0L before it.

Funny that the engine in question is a Navistar engine, not a Ford engine, but Navistar decided to use a Ford oil fill cap on their engine in their truck. LOL... strange....

It sucks they had the issues with these that they did, as well as the later big inlines. Our DT466 was a beast, 100% trouble free.. old inline Bosch pump, no electronics. Always started, always ran great, and never had any visible smoke in its stack and hardly ever any noticeable smell (and its 7sp manual gearbox still worked great!).

Now I see gas V8 schoolbuses running around laboring to pull themselves, and with smoke puffs in the exhaust and cracked leaking manifolds.

Thanks much for the reply. Good to hear they can survive in the right circumstances. This does fit with some of what I have heard elsewhere as well. Evidently a major cause of death with these was the in-cylinder injection for regens, leading to fuel dilution in the oil and mechanical failures (bottom end, valvetrain etc) as a result..... Obviously if the regen activity is stopped then that should no longer be a factor. No idea how many miles on the reman engine in this truck now but I guess the best case scenario is that it might not have been in there too long and if we can delete it now, it could still have some good life ahead.

Does seem to be one of those engines where there are a lot of bad experiences out there, but also some folks who get good long life out of them. I imagine the 500k-mile example you gave could make sense in part because the motor always works hard for that rig, which probably helps it. These 6.4L engines came out right around the time when it was becoming popular for folks to buy a diesel 3/4t pickup to use as a daily driver for lazy commutes, which I don't think was too common even just a few years earlier when 24 valve Cummins / 7.3L / 6.5TD were the diesel options as those were too loud and slow and harsh to want to drive to the office... The 6.4 is quiet and fast when running I guess, easy to live with so I imagine a lot of the failures could have resulted from not enough hard use and heavy activity of the emission system. Plus lots of em got tuned. No doubt between those two factors the conditions existed for them to have trouble.

It is surprising how many Ford pieces I have seen on this truck, considering it was produced at a time when the relationship between Ford and IH/Navistar had turned very bad, lawsuits and all. Ford had already kicked Navistar's motors out of its pickups years earlier by this point ... apparently this exact TerraStar truck was built in part as an attempt by IH to get a vehicle into the Class 5 market where Ford (with IH engines under the hood) had been dominating for years with the F450/550. Plus to use the 6.4L motor that IH had engineered but that Ford no longer wanted to buy.... And yet, under the hood, things like oil fill caps and coolant expansion tank caps are right out of the Ford parts bin, and there are Ford logos stamped all over the brake parts, wheels are the same 10-lug Accuride 19.5s that are otherwise only used on the HD F-series.... etc. I guess it takes a long time to really cut ties after you have been sharing engineering efforts for long enough.

Agree also that it is tragic that IH diesel engine production ended in failure with this engine and those produced at the same era, after they had built a reputation over decades as the best medium duty diesel engine line anywhere. The old DT's were (are!) great, and the 6.9/7.3 IDI and the 7.3 PSD/T444E were good too in their time. Still have all of those motors in the fleet and I will always trust them. Too bad IH made the mistakes they did and squandered all that good will. Granted, CAT ended up with a similar sad story (not to mention VW of course...)

Anyway, maybe this motor will be worth a shot if we can get it "fixed". I do like how easy it starts and quiet it runs. First CR motor I have ever owned -- I guess those are the benefits.

 

[oilhammer]

And I think they use Siemens, not Bosch, DFI, which was kind of odd.

Navistar is under Volkswagen stewardship now, mostly tossed over to Scania for development. VAG rolled it all under their Traton brand, along with MAN and Neoplan. Not sure if the new IH branded trucks are using a Scania-modified Navistar I6 engine or it is all new. Scania is famous for their very powerful V8 diesels.

 

[d24tdi]

Sad to say but I think a return to big gas engines in this size class of truck/bus is inevitable and will only continue. We have a couple GM 8.1L rigs in the fleet that we use mostly in the winter..... But even year round, the advantages over a modern diesel are obvious. Extremely simple and minimal maintenance, relatively long engine life, cheap to replace the motor if it ever needs it, easy to work on, cheap parts, and light weight. Think we will see the Ford 7.3L gasser and the GM 6.6/8.8 motors only become more popular when you compare to the modern diesel options. The only new MD chassis I would consider is the Ford F550-750 with 7.3L or an Isuzu N-series with GM 6.6.

Cummins has announced they will offer a gas version of the 6.7L B-series to compete as well, which I think is a pretty telling fact, first gas engine they will have ever produced. But it will be a DI turbo inline six which I think negates many of the advantages of the Ford/GM port injected naturally aspirated motors, in terms of simplicity/weight/maintenance/cost. By the time you get into direct injected turbo gassers you may as well get diesel efficiency too. Will be interested to see if they sell.

This is a tempting option as a way to repower the little TerraStar if the MaxxForce experiment ends up not working out.

https://www.theinfamousproject.com/shop/ford-7-3-godzilla-v8-motor-swap-package/

 

[d24tdi]

And I think they use Siemens, not Bosch, DFI, which was kind of odd.

Navistar is under Volkswagen stewardship now, mostly tossed over to Scania for development. VAG rolled it all under their Traton brand, along with MAN and Neoplan. Not sure if the new IH branded trucks are using a Scania-modified Navistar I6 engine or it is all new. Scania is famous for their very powerful V8 diesels.

I think you're right on the Siemens injection. The pump and injectors on the 6.4 appear to be unique to that engine.

Hey, glad to hear maybe I need to slap a VW logo on the front of this truck!

 

[oilhammer]

What sucks is, the only fruits of the VAG takeover of Navistar we are likely to see here is the upcoming Scout SUV, which is going to be electric, and thus, quite lame. You think Mitsubishi's final nail in the coffin was fitting the Eclipse badge to an ugly crossover was a bad plan, and Ford's slapping a Mustang badge on an equally fugly EV cross..er..."thing" just as bad, imagine the old IH Scout enthusiasts' angst over this. Maybe they'll go all J-6 on Wolfsburg, LOL....

 

[d24tdi]

Yeah, the new vehicles are all the same now. What makes a VW a VW versus a Kia or whatever? Hard to even say, all the unique engineering and design/aesthetics are gone. Turbo 4 banger CUV wheezers or EV's with interiors full of cheap plastic and huge screens, doesn't really matter whose badge is on the front. Mustang, Miata, and a few others are the rare exceptions to the rule.

Anyway, any other opinions on the Maxx 7 or 6.4 PSD motor from anyone on here who has run one? I am thinking of giving it a try. Got connected with someone who can provide the resources to address the initial problems that are keeping it off the road. Beyond dealing with that, I'm seeing advice to give a lot of attention to fluids and filters, change them at half the factory recommended interval, watch out for any signs of coolant loss thru the massive EGR cooler, watch for oil level increase from fuel dilution, bypass the CCV filter before it clogs, and otherwise run it as best I can. If I can get some miles out of it, it will easily be the quietest, smoothest, and most powerful engine in the fleet. So it will be a nice one to use for however long we can use it provided the reliability factors work (derates, faults, etc).

I have a good running T444E in a parts truck here that I am looking into options for transplanting if/when the Maxx gives up. It's about the same size and shape and I believe I can put together a recipe of parts to get the right SAE bellhousing on it to mate right up to the Allison 1000 that's already in this truck. Downgrade from 300hp to 190hp, but in a 20k GVWR truck I don't need more juice than our 80k GVWR semi has.

 

[oilhammer]

Spoke with an old friend who works at a municipality garage that takes care of all their equipment (from chain saws to police cars to snow plows) and he seemed to feel the biggest issue with all the modern diesels in trucks is that they are set up to be worked. When they are working hard, and loaded, that's when the emission control systems are at peak efficiency and not only doing their job but doing it fairly reliably. The problem comes when people drive them around with a light load, or too much idle time. And I'm pretty sure, to a new HO 6.7L Powerstroke equipped F-350, with a whopping 1200ft of torque on tap, a "light load" is anything under 10k pounds hooked to it's rear end.

That's why he said they don't do any diesel purchases on trucks any more unless they are for something that WILL be loaded ALL the time. I think this is probably why you don't see Sprinters with as many problems, because MB is using smaller engines thus insuring they are getting worked harder under most conditions. The Ford/GM/Chrysler deal has become a dick-swinging contest to see how impressive of a number they can display on a piece of paper, with no real thought for how it works out in the real world.

It's funny, because my 1990 F-350, which was the old IH prechamber 7.3L non-turbo diesel, had a Hypermax turbo kit installed on it when it was brand new. It bumped the HP from 170 to 185, and the TQ from 340 to 400. Despite it being saddled with the power-robbing E4OD-HD 4sp slushbox, and tipping the scales at 7200 pounds curb weight, that truck was dare I say downright "peppy" around town, and no matter what I put in or behind it, it handled it without breaking a sweat. I was hauling a tractor on a flat trailer behind it, and had to get up to speed quickly on a short on-ramp, and it pulled so hard it broke the ratchet strap we had holding the tractor's front axle to the trailer frame! Luckily the extra chain we had caught it and kept it from sliding right off on to the road!

And this truck did everything with an appetite for fuel that was pretty much the exact same as my '96 F-150. The 150 is a 4.9L/5sp, regular cab, long bed, 2WD. The 350 was not only the afore mentioned automatic, but a Supercab, and of course a dually.

My point is, it is hard for me to fathom a situation where most any person who owns a pickup for private use would ever truly "need" something that has DOUBLE the horsepower, and TRIPLE the torque, as my '90 did, let alone have 10 ratios in the transmission to handle it. But here today Ford will sell you one (they cost as much as a small house, mind you, but if you can stomach 10 years of $800 monthly payments, LOL...).

Be nice to get back to normal, and just have a decent, reasonably priced, reliable, and capable pickup choice again. Something that doesn't continually put the shortcomings of your manhood on public display.

This is why I think if I were to buy a new HD pickup today, I'd just go for the Godzilla engine. Plenty capable for any normal use, reasonable fuel economy compared to the Powerstroke, and won't really care if you are hauling around one fat chick or 20, it'll do it all just the same.

 

[d24tdi]

Spoke with an old friend who works at a municipality garage that takes care of all their equipment (from chain saws to police cars to snow plows) and he seemed to feel the biggest issue with all the modern diesels in trucks is that they are set up to be worked. When they are working hard, and loaded, that's when the emission control systems are at peak efficiency and not only doing their job but doing it fairly reliably. The problem comes when people drive them around with a light load, or too much idle time. And I'm pretty sure, to a new HO 6.7L Powerstroke equipped F-350, with a whopping 1200ft of torque on tap, a "light load" is anything under 10k pounds hooked to it's rear end.

That's why he said they don't do any diesel purchases on trucks any more unless they are for something that WILL be loaded ALL the time. I think this is probably why you don't see Sprinters with as many problems, because MB is using smaller engines thus insuring they are getting worked harder under most conditions. The Ford/GM/Chrysler deal has become a dick-swinging contest to see how impressive of a number they can display on a piece of paper, with no real thought for how it works out in the real world.

It's funny, because my 1990 F-350, which was the old IH prechamber 7.3L non-turbo diesel, had a Hypermax turbo kit installed on it when it was brand new. It bumped the HP from 170 to 185, and the TQ from 340 to 400. Despite it being saddled with the power-robbing E4OD-HD 4sp slushbox, and tipping the scales at 7200 pounds curb weight, that truck was dare I say downright "peppy" around town, and no matter what I put in or behind it, it handled it without breaking a sweat. I was hauling a tractor on a flat trailer behind it, and had to get up to speed quickly on a short on-ramp, and it pulled so hard it broke the ratchet strap we had holding the tractor's front axle to the trailer frame! Luckily the extra chain we had caught it and kept it from sliding right off on to the road!

And this truck did everything with an appetite for fuel that was pretty much the exact same as my '96 F-150. The 150 is a 4.9L/5sp, regular cab, long bed, 2WD. The 350 was not only the afore mentioned automatic, but a Supercab, and of course a dually.

My point is, it is hard for me to fathom a situation where most any person who owns a pickup for private use would ever truly "need" something that has DOUBLE the horsepower, and TRIPLE the torque, as my '90 did, let alone have 10 ratios in the transmission to handle it. But here today Ford will sell you one (they cost as much as a small house, mind you, but if you can stomach 10 years of $800 monthly payments, LOL...).

Be nice to get back to normal, and just have a decent, reasonably priced, reliable, and capable pickup choice again. Something that doesn't continually put the shortcomings of your manhood on public display.

This is why I think if I were to buy a new HD pickup today, I'd just go for the Godzilla engine. Plenty capable for any normal use, reasonable fuel economy compared to the Powerstroke, and won't really care if you are hauling around one fat chick or 20, it'll do it all just the same.

Agree, the horsepower wars arming the general public with vehicles that have capabilities beyond what a tractor trailer engine had a few years ago is insane. It also strikes me as funny that it's become "acceptable" for someone to use a six-figure pickup with extreme technical complexity and high maintenance demands/costs as their regular transportation, whereas if they were getting around in an Audi R8 or 911 or whatever (with similar purchase value and arguably less complexity and difficulty and cost of upkeep), they would be viewed as ostentatious and ridiculous. The modern pickup truck diesels are incredibly high performance machines that require the cab to be lifted for any kind of significant work -- completely outside the abilities of any normal owner or even many garages. How is that not equivalent to owning an exotic sports car, I don't know. That is what those rigs really are.

The old IDI motors were great when set up right. First place I worked had one as a shop truck, similar setup except it was a SRW F-250, but 7.3L with a Banks kit. Power for days, sounded great, quiet, smooth, clean exhaust. I think it would have outrun a stock 7.3L PSD. The E4OD trans was the sore spot of course.... Along with the endless leaks from the injector return lines and o-rings, glow plug relays, etc....

No question in my mind that for any commercial use short of an OTR semi, a gas engine in a new piece of equipment is the only way to go. A high-performance modern diesel is a choice made for performance not value. The equation was opposite a decade or two ago when the TBI gassers sucked with no power and terrible mileage, and the diesels were simple and great. Now the gas engine options are excellent and the diesels are out of control. Maybe some of the smaller-displacement diesels that are properly matched to the work they are doing can make sense. Sprinter, Isuzu cabovers, etc. But even then the cost equation will never favor a diesel, hate to say it as a diesel guy.

Here is something that is fun to play with -- Isuzu has a "fuel comparison" tool for speccing their trucks that allows you to look at relative costs for their gas vs diesel engine options in equivalent trucks. https://isuzucv.com/en/fuel_comparison

It is eye opening to see that the diesel usually only gets around 12mpg where the gasser gets 8-9, with cheaper fuel..... Payback period to offset the just additional UPFRONT cost of the diesel is around 200k miles usually. And that is only look at fuel expense..... doesn't even try to account for the much higher maintenance cost for a modern diesel vs a GM/Ford pushrod V8, or the cost of operating and maintaining an SCR system that needs to be fed DEF, common rail issues, or the lost productivity from any issue in the emissions system that leads to a derate or problem or puts the truck in the shop for an extended period of time, or time sitting doing a manual regen of a DPF, or, or..... I think the bottom line is that the diesel engine just never pencils out. Some folks would probably try to counter with longer engine life for the diesel but a modern gasser will go 200-300k, which I don't think is much less than the expected life of a diesel in a similar work environment.... And for what it costs to put one set of injectors and a DPF in a diesel truck in those 200-300k, you could replace the entire gas motor with a fresh one.

Motorcraft factory long block for a 7.3L Godzilla truck lists for under $6k on RockAuto. For that price you could replace the motor every few years and probably still be ahead of what it would take to keep a diesel equivalent going. And the cost of replacing the diesel engine if it fails, don't even want to know.

Maybe there is a resale value difference for the diesel but I wouldn't be surprised if in the upcoming years the market start to price in the risks/costs of buying a used emissions-era piece of diesel equipment, and the gas models become more sought after in the used market just for the sake of fewer variables.

 

[oilhammer]

Yeah, but the GM V8 gasser powered Isuzus will lunch a half dozen transmissions... we used to service a few of those, LOL. They also barf up catalysts, crack exhaust manifolds (like, constantly), and just for fun will break the exhaust manifold bolts off in the head. All on their own, you don't even need to touch them.

So yeah, the 6.0L V8 may be simple, sturdy, and thirsty, but it isn't without its faults. At least those are not cursed with that awful AFM crap. The half-ton trucks lunch lifters and cams like a fat guy through cookies. We've had three in one day here, LOL!!! If that awful system migrates up to the 8500+ GVWR engines, they're doomed. ChyrCo's Hemi was almost as bad (they're gone now).

Honestly, I really can't understand how GM continues to fail so bad at something that THEY literally pioneered. But between their V8s' problems, their terrible transmissions, and their rear axles with glass bearings in them....

We've got one of our techs rebuilding yet another rear end today:

Half ton pickup, with a V6, didn't even make it 100k miles.... This is a base model work truck, 2WD, regular cab, long bed, no frills (even has hand crank windows).

What went wrong????

 

[Lightflyer1]

The used 2011 F150XLT 5.0l I just bought used for $7500 (one owner, all maintenance records, no issues and 220k miles) was a much better deal than a new one. Especially for the occasional use it is intended for. It's fuel economy isn't great but for the limited times it actually gets used it doesn't matter. Went to Ford just to get away from the AFM issues I just went through on the 2007 Tahoe I bought. Redid all the lifters and such and gave it to my daughter who needed a vehicle.

 

[d24tdi]

Interesting, didn't have any idea the GM powertrains had those struggles. Been a Ford guy except when Ford doesn't build what I need, so I guess I just haven't paid attention. The 8.1L/Allison combo that is in our 6500/7500 "winter" fleet trucks has been bombproof, they just run, as long as you keep fuel in the tank. Truth is the fuel use isn't even as bad as one would think, usually about 7mpg running 20-30k GVW in the mountains. Our other rigs with IH DT466E and CAT 3126 get around 10-11 in the same conditions. Many % better but the 8.1 is respectable for what it is.

I have looked at a few Isuzu chassis with the 6.0L and like the way they drive. Haven't run into one yet for a good price that is the right wheelbase and GVWR for what I would need but I watch for them. I assumed the 6L90E trans in those was pretty good.... Sounds like not? Are those the ones that fail bad? The maneuverability and visibility of the cabover Isuzu setup is real tempting but sounds like sticking with the big block Kodiaks may be a better call vs the 6.0 in the Isuzus.

Back in the heavy shop I worked in years ago, we did see some of the older NPR trucks with the TBI 350 and 4-speed (I guess probably 4L80E?), those were lame for sure. The 6.0L/6spd Isuzus I have driven move very nicely though. The old models were a slam dunk in favor of the diesel, those old 4HE1 and 4BD1 were simple and tough. Not sure how Isuzu's new emissions-era diesels are holding up. The 4HK with common rail seems to have injector issues, but I guess all the CR stuff does at some point.

Crazy to see the rear end failures. This kind of issue seems hard to accept in a late model vehicle... I get it with pushing the envelope on technology and it feels like we can accept failures of new tech to some degree, but a differential or an oil pump failure makes no sense.... We've known how to build those for 100 years.

The gas 6.2L and 6R140 automatic in my 2014 F-250 run like new at 310k. Hope Ford's Godzilla 7.3 and 6.8 hold up well over the long run and don't have the issues that the GM gassers do, we will be looking for one of those some day. So far they still seem new enough to not be fully proven.

 

[oilhammer]

The GM slushboxes die frequently in PICKUPS that get driven around empty most of the time, LOL.... we've always got one of those laying around to trip over:

 

[oilhammer]

The 10sp in the Fords have a lot of issues and updates, but we've not seen any yet. They suck to drive, I know that. Exhausting.

The 6sp 6r80 were just a retweaking of the ZF 6HP26 transmission, aside from the early lead plate issues, usually limited to the 2010-14s, they seem to hold up reasonable well.

The 6R140 (aka, the 'Torqueshift 6") is Ford's own in-house HD unit. It replaced the old units, which were still extensions of the old E4ODHD, that became the 4R100W when FoMoCo changed their transmission naming convention. I think the 6R140 is pretty good. They benchmarked the Allison 1000 that GM has been using, identified all its weaknesses, and made it better.

We (thankfully) just don't get many HD trucks in here anymore. We stopped at 1-ton stuff anyway, although we did do a few minor things to some 4500 type trucks, and I got stuck doing drum brakes all around on an Isuzu NRR once, as well as an in-frame rebuild of an NPR after an injector went rogue and melted a hole in a piston.... that truck had over 600k miles on it at the time, so really couldn't complain.

 

[dieseldonato]

Up till a few years ago, I was a over the road heavy duty diesel mechanic. (No longer do road work.) I don't know of anyone that had one that didn't regret the purchase of anything 6.4L ih powered. Emissions delete were out of the question, can't go into ports or airports without it intact The trucks had a ton of issues besides all the emission related issues, extremely frail injection system, rad, intercooler and oil cooler issues. It's no wonder why ford ditched them. Had way less issues with the 6.0L. I was lucky and ended up with a dodge for my service truck. I'm a huge ford fan, but that 6.4l was/is a boat anchor. My uncle has all sorts of stories about them in pickups and medium duty trucks too. I wouldn't own one and don't reccomend them to anyone.

 

[Mozambiquer]

For passenger cars and also for the heavy equipment I operate for work, I have kept a hard rule up until this point of staying away from any post-2006 diesel equipment with aftertreatment systems. Especially those engines that are notorious for trouble.

However, I recently had a vocational truck come available to me that was such a good deal that it didn't make sense not to buy it. It is a 2017 International TerraStar (small medium duty truck comparable in size to a Ford F-550) with the infamous MaxxForce 7 engine. This engine is a close relative of the 6.4L Powerstroke used by Ford from 08-10. It has a terrible reputation in the Fords and equally bad in what I am able to read and hear from heavy truck owners.

I bought this truck knowing I might need to abandon the engine and chassis and transfer the vocational equipment installed on it to a different platform. I got it cheap enough that I can do that and still be looking good in terms of value, so that is the default plan (likely would find a clean older IH 4300 chassis with DT466E since that is what we run in most of our other trucks of this size and they have been great).

However::::::: this TerraStar with the MF7 actually fires right up and runs well. Engine has a Navistar factory reman tag on it, so it's had a motor already at some point, no idea when, but not too surprising given the known extreme short lifespan of this engine. 160k miles on the whole truck, which is a lot for the MF motor hence the replacement I assume, but no challenge for the Allison trans or other components, so probably plenty of life left in the rest of it. California truck, cab is clean, body is good, the PTO system works well, interior functions are all working, glass and rubber are even good. Transmission works well and the whole setup is pretty nice. It would need some rear brake work to hit the road, but that is standard cheap Ford F-series parts so no big deal there.

The engine starts easy, and runs nice and smooth. So now I am of course tempted to explore the question: is there still some life to be gotten out of this truck as-is?

It is missing the DPF -- DP sensor tubes and temp sensors are hanging there so it looks like one could be reinstalled, but they are $$$ and known troublesome, no doubt there is a good reason it's off of there now. I understand that there are alternatives out there to reinstalling it (even today, confirmed it). Those alternatives are expensive but not too much more than the cost of a new DPF, and would stop EGR operation as well. One way or the other I would have to put a few grand in to go one of those two directions right off the bat, since for now it has codes and derates of course with the missing aftertreatment. Luckily or unluckily this engine was part of Navistar's failed attempt to meet EPA2010 regs without SCR ("Advanced EGR" ), so it has none of those items to deal with. With EGR disabled and DPF eliminated it would be a "fairly simple" configuration -- although still HPCR injection with a high pressure pump that is known troublesome, etc....

SO -- in case there is anyone here who has some firsthand feel for this engine and can give some input -- here is the key question I have at this point. If I go ahead with emissions defeat on this engine, what kind of reliability and life can I reasonably expect from it? Can they last for a reasonable lifespan and be depended on?

The three paths I have right now are as follows.
1) Put in the necessary work to get the truck on the road w/o EGR or aftertreatment as-is, and then run it for whatever life I can get from it, hopefully for a number of years and miles.
2) Remove vocational equipment from this chassis and swap to another chassis, then scrap this chassis even though it seems to run pretty good.
3) Swap a different engine into the TerraStar chassis (Cummins fits, probably could figure out some options with a T444E or some kind of gasser as well).

If it is feasible then I would be tempted by #1, knowing that the other two options would still be possible down the road if the MF7 had a major failure. But maybe someone will tell me that it makes no sense to even put a dime into this engine, and get rid of it while I can. It may have value as a running used engine.

Appreciate any thoughts from those who know this motor. TIA!

Oof, and big oof... I've worked on a bunch of those, seen a lot of failed engines with less than 100k miles on them. They're absolutely garbage. Anything maxxforce, but especially the 7.

 

[dieseldonato]

Oof, and big oof... I've worked on a bunch of those, seen a lot of failed engines with less than 100k miles on them. They're absolutely garbage. Anything maxxforce, but especially the 7.

We all thought the 13 and 15L maxfarce was bad....

 

[Mozambiquer]

We all thought the 13 and 15L maxfarce was bad....

Yep... But in my experience, the 7 was worse.

 

[d24tdi]

^^ Thanks for the replies -- this is the kind of direct experience info I was hoping a few folks on here might be able to share regarding the Maxx 7. I have spent all of my time around the pre-2007 engines and have no familiarity with this unit.

So @dieseldonato and @Mozambiquer if you were in my position now, what would you do? I already own the truck and am glad to have it -- the components on it (tank, liftgate, PTO, vacuum transfer pump, all with minimal use) add up to much more value than I paid for the entire unit. I basically got the entire vocational body at a large discount, plus the IH TerraStar truck chassis (with fresh rubber!) that they are installed on for "free". I guess that alone tells you how bad most folks want to stay away from this engine. Fortunately I am in the position to be able to swap these components over to a different chassis if needed, so for me it was an easy decision to pick it up at this price even if the chassis is a throwaway.

Anyway, now it's here (too late to run away!!) and it appears to be in decent running condition apart from the missing DPF. And it does have a reman complete motor in it (unknown miles on that). So here are my two options at this point:

1 - Quit while I'm still ahead - take the stuff off this truck to transfer to another chassis that I know I can trust; scrap or sell the TerraStar and its MF7 engine before anything can go wrong and start costing $$$ or downtime.

2 - Spend the money ($1-2k) on the initial needs that would get this truck repaired and on the road, and then try to run it until it has a major failure or proves itself too unreliable to send out for use. That would mean doing one of these two steps:
2a - put a DPF back on it and try to make it work with full emissions operational.
2b - tune it to run without the DPF and run it that way. No problems in my area with ports or other compliance concerns (at least not yet).

If I do either version of option 2, I still have the choice to dismantle the truck later, or repower with a Cummins or other engine. I do like the IH cab and the truck is nicely configured. Option 2a or 2b both could be done for a grand or two, so not a zero-cost experiment but not expensive if it ends up giving me a truck that can be used. Cost is about the same for either scenario, although if I go for 2a, then I think it is likely I would run into whatever problem caused the PO to pull the DPF off of this in the first place so probably have something else to resolve.... or an unknown path to fixing it.

Right now option 2b is what I am working towards. Am I nuts for thinking about this? I think my biggest question is, after modification, can I expect any kind of decent reliability or lifespan from this engine. Sounds like with the fuel system and other base engine concerns, maybe not?

Appreciate the advice.

 

[Mozambiquer]

^^ Thanks for the replies -- this is the kind of direct experience info I was hoping a few folks on here might be able to share regarding the Maxx 7. I have spent all of my time around the pre-2007 engines and have no familiarity with this unit.

So @dieseldonato and @Mozambiquer if you were in my position now, what would you do? I already own the truck and am glad to have it -- the components on it (tank, liftgate, PTO, vacuum transfer pump, all with minimal use) add up to much more value than I paid for the entire unit. I basically got the entire vocational body at a large discount, plus the IH TerraStar truck chassis (with fresh rubber!) that they are installed on for "free". I guess that alone tells you how bad most folks want to stay away from this engine. Fortunately I am in the position to be able to swap these components over to a different chassis if needed, so for me it was an easy decision to pick it up at this price even if the chassis is a throwaway.

Anyway, now it's here (too late to run away!!) and it appears to be in decent running condition apart from the missing DPF. And it does have a reman complete motor in it (unknown miles on that). So here are my two options at this point:

1 - Quit while I'm still ahead - take the stuff off this truck to transfer to another chassis that I know I can trust; scrap or sell the TerraStar and its MF7 engine before anything can go wrong and start costing $$$ or downtime.

2 - Spend the money ($1-2k) on the initial needs that would get this truck repaired and on the road, and then try to run it until it has a major failure or proves itself too unreliable to send out for use. That would mean doing one of these two steps:
2a - put a DPF back on it and try to make it work with full emissions operational.
2b - tune it to run without the DPF and run it that way. No problems in my area with ports or other compliance concerns (at least not yet).

If I do either version of option 2, I still have the choice to dismantle the truck later, or repower with a Cummins or other engine. I do like the IH cab and the truck is nicely configured. Option 2a or 2b both could be done for a grand or two, so not a zero-cost experiment but not expensive if it ends up giving me a truck that can be used. Cost is about the same for either scenario, although if I go for 2a, then I think it is likely I would run into whatever problem caused the PO to pull the DPF off of this in the first place so probably have something else to resolve.... or an unknown path to fixing it.

Right now option 2b is what I am working towards. Am I nuts for thinking about this? I think my biggest question is, after modification, can I expect any kind of decent reliability or lifespan from this engine. Sounds like with the fuel system and other base engine concerns, maybe not?

Appreciate the advice.

International made a kit to replace the maxxforce 7 with an ISB Cummins, which is a good engine. But, since you own the truck and got it cheap, it would not be a bad idea to use it until it blows again, then decide what to do with it. You can try to keep up with maintaining it and keeping clean fuel in it, and it may last a bit longer. They also don't like constant idling either.

 

[dieseldonato]

I'm inclined to agree with Mozambique, run it till it blows, then repower or get another truck + swap components. I'd opt for a full delete in this case. The fact is has a reman engine in it is just another testimony to how crappy these engines are. When it does give grief, I'd personally swap it for the cummins vs swapping everything over to a new truck. No one is going to give you anything for a chassis with a blown up/ problematic 6.4l

 

[dieseldonato]

Yep... But in my experience, the 7 was worse.

Agreed, much worse by far.

 

[d24tdi]

Thanks to both of you, appreciate the input. Sounds like the consensus is may as well give it a shot, get it back on the road and see what life it can give. For the minimal cost to do that, not much to lose even if it pops the motor in a few months or a year.

Luckily this is going to be kind of a specialty limited use truck in our fleet (mostly run larger straight trucks but need one small unit to get into tight spaces from time to time) so maybe if we are only doing a few thousand mi per year, we'd get a year or three out of it at that rate if we get lucky. We'll focus on good maintenance and clean fuel for whatever running we can do with it.

I agree it is amazing to see a reman engine in a truck like this with 160k miles, especially since the engine looks like it has already been in there for a while so probably was put in around 100k if I were going to guess (it's at least been in there long enough to get some oil leaks already LOL). This truck was at auction with an identical sister truck ... and that one also had a reman in it already, with similar miles. At least this one runs, that other one did not. From everything I am reading and hearing, these IH factory reman Max7 engines are not improved or updated in any way and are subject to exactly the same failures as the original engines, so are expected to have the same kind of short and troublesome lifespan. What a joke.

The Cummins swap seems like an easy answer when the time comes.... I don't believe IH makes that kit anymore but I imagine any wrecked later year IH with the Cummins in it would be able to be a donor of the engine and the parts to interface with the IH chassis. IH cab (visibility, ergonomics etc) is the best IMO so if the truck can be made to work a while with the Maxx and then something else down the line, I would be happy about that. I also would imagine a VT365 or VT275 would be a fairly easy swap since those appear to share most of the architecture with the 6.4/Max7. Or a T444E would be tempting as well... similar size/shape. The I6 Cummins would be a squeeze in the little TerraStar engine bay, I think they are probably easier fit in a larger DuraStar 4300 etc.

Ask me in a year how this all turned out......