Anyone have mercedes CDI knowledge?

2002tdi

Vendor
Joined
May 8, 2011
Location
NORTH BALTIMORE OHIO
TDI
2012 jetta premier DSG
Looking at buying an 08 Mercedes GL320 3.0 diesel. 7 speed auto. my wife wants something with 3rd row seating and I am thinking this is the best bet. any negatives?
 

IndigoBlueWagon

TDIClub Enthusiast, Principal IDParts, Vendor , w/
Joined
Aug 16, 2004
Location
South of Boston
TDI
'97 Passat, '99.5 Golf, '02 Jetta Wagon, '15 GSW
No GLs here, but Corey (cevans here) has a 2011 R-Class that shares the drivetrain with the GL. It's his second one. Both have only had minor issues. The 2011 has about 80K on it, the 2007 he had previously (now owned by btcost here) has over 100K on it. Only issue that vehicle has had that I know of was a problem with the turbo actuator.

Leaking oil coolers are very common (we have a kit for that), as are injector seals in the OM642. Corey had to fix a botched replacement of one of those in his E320 CDI (same engine). The OM642 has proven very robust, they cover tons of miles in Sprinters.

Overall, I think the GL or R-Class are good options. Just keep in mind that as they age they'll need repairs, they're more complex than an '02 Jetta, and parts can be more expensive, although some things aren't.
 

oilhammer

Certified Volkswagen Nut & Vendor
Joined
Dec 11, 2001
Location
outside St Louis, MO
TDI
There are just too many to list....
All the V6 diesels I have seen hold up amazingly well, with very little attention ever needed. The later SCR equipped ones have some problems here and there related to that system, but the engine proper is still robust and durable.

If the fleet guys can beat the Sprinters for a half a million miles (literally, not kidding) and they hold up, then a well cared for M or GL class should be no sweat.

I have never seen on of the 7sp G-tronic transmissions fail either.

The durability of these was largely why I made the choice to buy a new Sprinter when I needed a van. I went with the 4 cyl version, but I have faith it will hold up just as well. MB still does diesel very well.

You can expect a few niggling things on the rest of the car, some of it is simply because they love to make things more complex than they need to be. But they are pretty nice to drive. I am not an SUV fan, but those are probably better than most to drive.
 

Kevinski4

Vendor , w/Business number
Joined
Aug 31, 2007
Location
Nebraska
TDI
.
I tuned an '07 ML320 and an '08 GL350 this week. Totally transformed how they drove and shifted. Stock, they had decent torque down low, then it just makes noise til it shifts. Stage 1 tuned they pulled HARD all the way up to 4000 while it just clicked through gears until you got into the 'lose your license' speeds and it was still pulling. I might need to find myself one now...
 

2002tdi

Vendor
Joined
May 8, 2011
Location
NORTH BALTIMORE OHIO
TDI
2012 jetta premier DSG
I tuned an '07 ML320 and an '08 GL350 this week. Totally transformed how they drove and shifted. Stock, they had decent torque down low, then it just makes noise til it shifts. Stage 1 tuned they pulled HARD all the way up to 4000 while it just clicked through gears until you got into the 'lose your license' speeds and it was still pulling. I might need to find myself one now...
What software do you use? seems like they respond really well with a tune.
 

B3achbum

Veteran Member
Joined
Jul 7, 2015
Location
North Florida
TDI
(Nigel) 2004 jw GLS 5sp / +332K miles, (Hildegarde) 2008 R320 CDI / +132K miles
GL / ML / R diesels

I bought a 2008 R320 springtime this year, at 120k miles. Now have 131k.

The three models share many systems, from drivetrain and suspension, to control systems.
If you're intending to keep it up yourself, the GL is easiest to work on because access to the motor will be the best of the 3.

The ABS system is currently giving me some grief, have replaced the indicated sensor with no joy yet... Will have a hard look at the harness this weekend, before considering the controller.

Before buying, you really must get the VIN to your local dealer and get whatever service highlights MB has on the vehicle. If you're looking at one with 100k+ miles, chances are fair the most expensive jobs have been done, but you don't want to go into it blind.

The oil cooler seals job is 15 hours book, which means for mortals it could take a week off work to cover the learning curve for a first-timer... Parts (ALL of them!) for this job can be had from Peter (above) for $100 or so, but it's a long, detailed job.

If the transmission controller fails, I think there are more affordable options available now, than when the problems first came to light. Replace the fluids in the boxes if the history is unknown.

I bought my car for less then I paid for the mk4 Jetta wagon! (About the same miles on the clock back then, too) The depreciation to on MB is a great boon, for those of us who "ain't skeered"! My Jetta is at 330k now, and I figure the R ought to go that far at least.

Looking forward to getting a tune on it. In addition to Malone, you have the option of Green Diesel Engineering, who are well trusted over on MBWorld.org, Sprinter, and Jeep forums.

You may have noticed the tire trend for SUVs and trucks are toward low profile? For these trucks the 19x8.5 tires are sticky And H-rated And run-flat. Average life is 25k miles unless you forget to rotate religiously, in which case you will be buying more frequently.

Code reading: Carly reads up to 66 of the ECU/controllers, depends on installed options.
$60 for the download, can use the BAFX OBD2 Bluetooth dongle you use for Torque app.

I'm reminded, I owe cevans a how-to on the power steering fluid leak. This is definitely an MB thing... The Jetta has Never used ps fluid!

I really like the car/van/truck. To me, the R is the B5.5 wagon gurus like Scott Dewitt could specially construct for you back in the day, if time/cost was no object (AWD). But the R is bigger, beefier 3 rows seating- air suspension in the rear! 3300# tow rating... I have four children, and my oldest son is bigger than I am now, so the roominess is just great.

Hope this helps,
Tom

Non-sequitor, but really fantastic thread in case anyone reading hasn't seen this:
https://grassrootsmotorsports.com/f...g-the-unicorn-of-my-destruction/110824/page1/
 

Owain@malonetuning

Associate Vendor , w/Business number
Joined
Jul 1, 2016
Location
Vancouver
TDI
PD jetta wagon
We've been doing a lot of Mercedes over the last year and a half or so, particularly sprinters and I'm the poor guy that's been learning about them. The powergate 2 (flashzilla 2) will work to port flash these pre DEF mercedes, distributors like Kevin do a lot of them too. All DEF equip (09 and newer, and 10+ sprinters) have to be bench flashed and SCR modules cleared prior to tuning. A lot of our distributors also want to avoid them, because they can be a royal PITA, particularly the DEF stuff.

At this point we have multiple MBSTAR clones circulating as rentals and for in house R&D to help keep the hair loss to a minimum. An 08 should be fine, I'd avoid 09-11, emissions on newer ones seems better (after they tested and modified software on the public for a few years) but they're still failing regularly. We deal with a local shop that services 20-30 sprinters/week and they said that fleet owners are averaging around 8-12K/yr per vehicle in repairs, most of which is emissions and brakes. Mechanically the motors and transmissions are pretty sound, I'm sure oilhammer sees a ton of them for regular minor maintenance.

I'd go for it if the price is right, they're not common vehicles and there's nothing on the market quite like them.
 
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clacker

Veteran Member
Joined
Mar 29, 2000
Location
Oxford Mills, Ontario, Canada
TDI
2015 Golf Wagon TDI DSG Trendline, 2000 Jetta TDI auto, 2008 Mercedes R320, 2006 smart fortwo cdi
I am 6 years into owning a R320 CDI (bought used 4 years old with 60k miles, now at 165k). Needed the room for family roadtrips and two young kids. I do not regret it. However, they are not for everyone. If you cannot maintain it yourself, expect big bills to keep it. They are very expensive in the retail field. If you cannot supply your own parts move on...I have done the air bags which is to be expected every 8 years or so, one shock which surprised me. Cleaning level sensors every year, just did the lower control arm bushings. Sway bar links, steering rack repair which required a very large MB dealer to work on (small dealerships had no clue how to do it or even what part to order). The engine on mine has been fabulous, just a constant weep from the crankcase blowby system that plagues all of them. There is lots of plastic parts on the engine and it gets hot under the hood, all that stuff will degrade at some point. If you cannot get one under $10k and budget a couple grand each year for repairs this is not your vehicle. Transmissions have issues with torque converter and valve body problems, the fluid does get dirty rather quickly in them too (40-50k intervals for servicing would be good, 100k is too long). Anything transmission related is pretty much dealer only work or a specialist with a Star set up and vast knowledge. I gave up trying with smaller dealers, mine is doing strange stuff when it is really hot, weak 1-2 shift but not able to visit the big dealership right now. Took 4 dealerships to get a proper wheel alignment...with height adjustment. They eat tires when the ride height is not checked.
I would say the biggest problem with them overall is getting parts, maybe the GL has a better product selection but the R is near impossible to get common parts for it. I have to import from the USA well ahead of the repair job to ensure they are correct and in stock. There are many things getting stocked on the engine but suspension bushings are still hard to track down and used parts are non existent compared to VW.
 

B3achbum

Veteran Member
Joined
Jul 7, 2015
Location
North Florida
TDI
(Nigel) 2004 jw GLS 5sp / +332K miles, (Hildegarde) 2008 R320 CDI / +132K miles
Trans fill level

The R has the steepest install angle for the transmission.

After having done it with the body level (vs. the transmission being level) I had extra 2 quarts left from the Idparts service kit.
I'm going to top off with the body at a decline / get trans level, and get 1 more quart into it if I can.

I followed the (probably best known) DIY video on the NAG2 fluid change, the author is an Aussie ex-motorcycle racer. Drained trans, torque converter, and cooler. When I asked my indie about it, was told they usually just drop pan change filter and replace what comes out (about 5 qts).

Point is, if servicer doesn't do it this way, is about 1/3 to almost 1/2 of the fluid left in the system. He didn't seemed concerned about the fluid level in mine, but I've had some misbehavior in the last week. The ABS issue will set codes in the transmission as a side effect.

Yeah, agreed it's your wallet or your time with these cars.

Sounds like you have the airmatic suspension. I avoided that, just have the bags in the rear.

Through the current issue, I discovered I much prefer turning the ESP system off. The steering is much more direct-feeling, without being harsh.

With the blowby, yes, these cars benefit even more from a ProVent or similar, than even the ALH. I have most of the parts collected to do this. Need to figure a good place to fit the filter, and route the hoses...
 

clacker

Veteran Member
Joined
Mar 29, 2000
Location
Oxford Mills, Ontario, Canada
TDI
2015 Golf Wagon TDI DSG Trendline, 2000 Jetta TDI auto, 2008 Mercedes R320, 2006 smart fortwo cdi
I have not found a drain on the torque converter yet, all my older Benz's have them but never found it on the R. I have read it likely does not have one...if you can confirm that you have a drain it is the first I know of on the R320. What year?
I do 5 liters per trans service, measured and by checking level. The couple I have serviced were all the same (R500 too). Fluid was always dark if they went 100k miles. All have towed stuff I asked. I tow stuff too, not much now that I have a truck too but used to tow a trailer often on up to a car dolly and 4000lbs a couple times, it was awesome but I took it slow and easy. A tow dolly has very little tongue weight, just a lot of mass when loaded. Airmatic is so good for towing!
 

B3achbum

Veteran Member
Joined
Jul 7, 2015
Location
North Florida
TDI
(Nigel) 2004 jw GLS 5sp / +332K miles, (Hildegarde) 2008 R320 CDI / +132K miles
TC drain

Yes, indeed - there is a drain plug on mine.
(, And the kit from IDParts supplies one)

For this I had a buddy look for it through the cover, as I turned the crank over.
When I looked at it after he found it, I didn't see it right away.
It was on side of torque converter I hadn't pictured.

I might not be describing well. Think of the doughnut shape of a TC, I thought it would the back-facing surface but it's on the front.
(I think - but I could have it backwards)
It's not absolutely on the outer tangent edge of the doughnut.

It's been a while since I did this, and sorry for the delay!

I'll be sure and let you know how much more fluid I can add with the trans level to the ground. I feel like the fluid level from the factory would have been the same regardless of the model the box was destined for.
So levelling by the transmission box rather than the body would probably be best. As inconvenient as it is...
 
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