B5.5 4mo BHW swap

oilhammer

Certified Volkswagen Nut & Vendor
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outside St Louis, MO
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There are just too many to list....
Given the doom and gloom of the future of diesels, I've decided to not only horde any that I can, I've decided to convert one of my several gasoline powered Volkswagens to diesel.

The subject is my 2004 Passat wagon, which has the AWM 1.8t engine, automatic transmission, and 4mo AWD system (Torsen).

I've obtained a crashed 2005 BHW sedan, and I am looking for some pointers on what all I will need from this car before I scrap it. I know some here have done this sort of thing. The main difference I see as being potentially problematic going forward is the 4mo part, but more on that later.

I have already gotten:

the complete running engine, engine harness all the way to the ECU

the ECU

the fuel lines running across the firewall down to the rear of the car

sound deadeners on firewall

starter

brake booster tube and firewall grommets (different from the AWM)

cluster

trans controller

air cleaner and related plumbing


Now, I know the AWM's transmission (which is working fine BTW at 215k miles) is geared lower, but is otherwise the same basic ZF 5HP unit. For the time being, I'd like to just leave it alone. Hopefully I can swap in the TCM from the BHW which should make the shift points behave better because as it is now if you stab this gasser on the highway it will happily jump down a couple gears and let that AWM sing all the way up past 6k RPM, and pulls pretty good past 4k RPMs, right around where the BHW lays down and dies. So I NEED the shift points to be diesel-friendly, especially if the over all gearing has the engine spinning 600 RPMs faster at 80. I've thought about trying to swap the rear Torsen section of the 4mo trans over to the diesel trans, but then I'd also I'm sure have to change the rear differential, and if I am going to go through all that nonsense, I'd just try and source a manual gearbox. So for now I'd like to make the existing automatic work.

The lift pump is another concern. Since the fuel tank is different, the pump/sending unit arrangement is different, and there were no 4mo diesels sold here. Will the AWM's in tank fuel pump work to pump diesel to make the tandem pump work? If so, how will it be controlled? I have not yet investigated the control circuit for gas vs. diesel in tank pumps. I have also not yet looked into the ECU box on the AWM to see if all the same plugs exist on the car as on the BHW's harness. There are several color coded plugs. Luckily the trans harness is completely separate, as is the rest of the harness for the front of the car. So the engine stuff is TOTALLY independent of anything else, hoping most of this will be plug 'n play.

Going to have to blitz the immo and VIN from the ECU, not sure what I will have to do with the cluster. I'd like to roll the odometer forward though, as the donor car only has 98k miles. I will likely need to recode the ABS controller too, but that shouldn't be an issue.

The donor car had a HARD crash on the left front, as such it bent the power steering pulley which is different as well as the charge air cross tube, which is also different. So I still need to find those two items.

I just want to make sure there is nothing else I need from the donor car before I take it to the scrapper, then some pointers on the actual swap.
 

Ifixit

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Feb 13, 2011
Location
Waitsfield, VT
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97 B4 Passat GLX TDI Wagon & 99 Golf & 05 Passat 4motion Manual & 04 Audi A4 Avant
Awsome!
Cant wait to see this unfold Ive often stood under these and daydreamed this swap with the 5hp19..
may be possible to convert diesel trans to awd...
 

deegingerkid

Beware the Ginger! Vendor
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The Left Coast
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"Blurple" 2000 New Beetle 5M 2006 Jetta has been SOLD
Matt and I have all intentions of doing this same principle with an Audi Allroad. :D

I look forward to your updates!
 

dogdots

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Sep 4, 2002
Location
Kansas City
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Brian, I have some A4 Quattro driveline parts available if you want to convert to 5 speed manual - gearbox, rear diff and subframe assembly, and axles. I don't have a spare 3rd pedal or shifter though. PM me if you want it, maybe I'll trade you for your free Beetle if you still have it :p If I remember correctly the Audi donor was a 1.8t gasser.
 
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vwztips

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Greenville, SC
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2005 Passat GLS Wagon TDI 5 spd manual w/BSM delete 2011 Tiguan TDI/DSG 2005 Audi A4 Avant 6MQ TDI 2011 BMW X5 35d
I can't help much on the automatic side, but have converted a GLX Passat, Allroad and C5 A6 from gas to diesel and automatic to manual.

For starters I left the fuel pump alone in the gasser AllRoad and installed a T in the engine bay to reduce the pressure. Have not had any issues with it yet.
 

Reddok

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Feb 18, 2010
Location
Hamilton, Ontario
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'00 Jetta TDI 01M, '02 Jeep Liberty Renegade ALH TDI swap
I'm pretty sure the transmission controller will not be happy with the gear ratio differences. Can anyone program the TCU's for different gear ratios? I just converted a Passat GMR 5HP19 into a 5HP19FLA (Quattro) for use in my A4 B6 BHW swap. That should allow me to use the BHW ECU and GMR TCU together in the A4.
 

Reddok

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'00 Jetta TDI 01M, '02 Jeep Liberty Renegade ALH TDI swap
Also, did you take the accelerator pedal from the Passat? I believe they are different part numbers.
 

oilhammer

Certified Volkswagen Nut & Vendor
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Location
outside St Louis, MO
TDI
There are just too many to list....
Did not realize the accelerator pedal was different, but ETKA does show a different part number... no idea why VAG does stuff like that. Thanks for the info, I will get that out of the car for sure.

You said you changed the FL to an FLA, I thought about that, is it just a matter of swapping the Torsen section off the back or is it more involved than that? Also, this would mean I'd need to swap the rear diff too, yes?

Cannot seem to find much info on gear ratios on these. Most web searches concentrate on the manuals, not the automatics.
 

Reddok

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'00 Jetta TDI 01M, '02 Jeep Liberty Renegade ALH TDI swap
Changing the FL to an FLA isn't as easy as it sounds. When I searched I found exactly zero people who had ever done it.

My goal was also to be able to retain my stock A4 rear differential - the 5HP19FLA has two sets of reduction gears in it that match the transmission output to the differentials. I ended up choosing a 5HP19FLA from a B5 A4 that had reduction gears in it that would allow it to match the GMRs 3.08 final drive ratio. I had to order an output gear and output housing shell from Germany to make this work.

You might be able to find a TDI auto trans and controller overseas that would play nice with the BHW ECU for less money. That and in order to put the 5HP19FLA AWD section on to the 5HP19, you have to swap the main output shaft of the transmission - which involves completely disassembling two transmissions.

All that work and $$$ and I'm still not 100% sure it will work when I finally get my swap done. If you can find ZF's ELCat online it will list all the types of 5HP19FL/A's and their gear ratios.
 

oilhammer

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Location
outside St Louis, MO
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There are just too many to list....
Yeah, that is kind of what I was (am) afraid of. I think I want to try the GMR trans' TCM in the car as it sits right now, with the running/driving AWM engine, just to see what happens. I really doubt there is much difference between the two, just the shift and lockup mapping. All the inputs and outputs are the same, and are all broadcast across the CAN just the same. The VSS signal is through the ECU, not the TCM (nor the ABS, like some other newer VAG platforms).

I know there is soft coding differences FWD vs. AWD, but I really can't think of what real difference that could make other than perhaps they hold the gears out a wee bit longer to compensate for the extra drag of the extra driveline. The Torsen is purely mechanical, it doesn't care about any electronics. Not like a Haldex that has a controller and needs to communicate with the other modules in order to do its job.

I really don't want to have to swallow the added expense and work with a manual swap right now, although I would prefer one.

The AWM is running fine, but it has developed the all-too-common oil leak at the chain tensioner, and at 215k miles I really think that part is on borrowed time anyway. I hate to spend ~$450 on that part (in addition to all the rest of the timing belt and related bits it needs to) if I can make this BHW work on the cheap.
 

Reddok

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'00 Jetta TDI 01M, '02 Jeep Liberty Renegade ALH TDI swap
I suspect what will happen is the transmission will go into limp mode and throw an incorrect gear ratio code due to the transmission gears not being the same as the BHW.

You are correct about the torsen. It has no sensors/solenoids and should function normally. I am wondering what will happen with the traction control - I believe it is controlled by the ABS module which is staying in the A4. Hopefully it will behave the same as before while still talking to the BHW ECU.
 

Mikkijayne

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Location
Devon, UK
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Audi S8
I suspect what will happen is the transmission will go into limp mode and throw an incorrect gear ratio code due to the transmission gears not being the same as the BHW.
This is an interesting point - its well known that this happens with the 5HP24, as they have different internal ratios. Swapping TCUs for different ratio versions doesn't work.

However, many years ago I did a lot of research on the 5HP19 and found that all the different versions have just a single set of internal ratios and they changed the overall ratio just with the final drive. In theory you could make a gas version in to a diesel version just by swapping the output shaft and differential. Since the TCU monitors input and output RPM before the final drive gears (and doesn't care about VSS afaik), in theory they will all be the same, regardless of road speed, so the TCU swap might just work.

It'll certainly be interesting to see what it does :)
 

oilhammer

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outside St Louis, MO
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There are just too many to list....
That is what I am trying to find out: the 5HP19FL/A ratios. If the actual 1-5 (and R) gear ratios are the same and just the final drive is different, then the TCM should not in theory know the difference and its predicted gear ratio, as measured from input shaft speed to output shaft speed, will remain the same.

I know in many other conventional automatics that is the case. The planetary gearsets are the same, they just change the overall gearing with the final drive.

As for the ABS, the soft coding on the Bosch 5.7 or whatever it is allows for gas or diesel, FWD or AWD, etc. in any combination. So that should not be a problem. This is fresh in my head because I just installed a new unit last week in a customer's car.

Right now I am fixing up a 2004 FWD AWM/automatic sedan to resell. I need to take the front seats out and clean the floorboards from the [all too common] neglected drains, etc. So I'll be at the TCM anyways. I am going to plug the TCM from the diesel in and just see what it does. If it completely spazzes out on this car, then I will know it won't work on my 4mo wagon either and I'll have to look into doing something else.

I also need to get the trans code off of the 4mo car, and then pursue any gear ratio information. ETKA does not show much.
 

compu_85

Gadget Guy
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Location
Springfield VA
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... None :S
I was wondering about the incorrect gear ratio fault as well... but if it's not measuring final output speed perhaps the TDI computer wouldn't know any better?

As far as what to save... I'd remove every nut, bolt, clip, and wire from the donor car. It's easy enough to throw the bits into labeled boxes then get rid of them later, rather than find you need some little part VW wants $200 for in a couple months.

Could you put slightly taller tires on it to help make up for the gearing difference?

-J
 

oilhammer

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There are just too many to list....
I don't like the look and feel of taller tires, nor the constant worry of tearing up wheel well liners, etc. And since this will be a utility vehicle (Sport Utility Variant.... that is what I already call it :D ), and won't be used much for high speed long distance runs, I am not too worried about the lower gearing. Right now, in 5th gear + lockup the AWM spins along at 80 MPH about the same as my ALH 5sp Golf. So it isn't like the BHW will be struggling or off the meaty part of the power hump... but it needs to STAY there on hills or when you accelerate. Even in Tip mode, the current setup will override driver input and downshift. I've tried to find a TCM soft coding that would eliminate that very annoying behavior, but as of yet have been unsuccessful. I really do not want to HAVE to drive the car in Tip mode all the time just to keep the engine from redlining all the time, though. So even if I did do away with ANY TCM gear selection input no matter what, it would still be somewhat lame.
 

Mikkijayne

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Audi S8
Elsawin tells pretty much everything about the transmission specs. Post up the trans codes and I'll look them up for you :)
 

compu_85

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Perhaps you could just use the TDI's trans computer. Easy enough to plug it in right now and see what happens.

-J
 

oilhammer

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outside St Louis, MO
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There are just too many to list....
Perhaps you could just use the TDI's trans computer. Easy enough to plug it in right now and see what happens.

-J
See post #1 :p

But I am going to try that first in a different AWM car hopefully this week just to see what happens.
 

Mikkijayne

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Audi S8
Elsawin is being somewhat belligerent today and not showing the FAL at all. However, it has confirmed that ratios for all 5HP19s are the same:

1st 3.665
2nd 1.999
3rd 1.407
4th 1.000
5th 0.742

Final drive is 3.091 or 2.727 but it is declining to tell me which is in either the FAL or GMR.

Most vexing.
 

Reddok

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'00 Jetta TDI 01M, '02 Jeep Liberty Renegade ALH TDI swap
3.0911 is the final drive for the GMR transmission.

FAL code gear ratios are 3.67, 1.99, 1.41, 1.00 and 0.740 with a 4.10 reverse.

Final drive is also 3.0911

GMR transmission has a special torque converter and valve body for diesel application.

I think you might be OK with the gear ratios - but you might run into an error code for the torque converter because the gas converter will slip more than the diesel.
 

Reddok

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'00 Jetta TDI 01M, '02 Jeep Liberty Renegade ALH TDI swap
Well someone is wrong.
About what? Mikkijayne's information is correct. The 2.727 may be the rear diff ratio for the FLA. I only have the ZF information which doesn't include anything outside of the transmission.
 

JFettig

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B5 Passat, 2010 Jetta
I think its group 015 in engine measuring blocks that outputs wheel speed, log that and engine RPM, back calculate it. I'm sure the gasser has similar measuring blocks. If they're the same, it'll be obvious.
 

oilhammer

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There are just too many to list....
About what? Mikkijayne's information is correct. The 2.727 may be the rear diff ratio for the FLA. I only have the ZF information which doesn't include anything outside of the transmission.
From your two posts I really can't tell what the difference is. But I KNOW the two transmissions are geared differently. Whether it is in the actual gearsets or the final drive, or both, is unclear.

Mikki stated all 5HP19 gear ratios are the same. (post #21) You said the final drive ratio is the same. (post #22) Well, something has to be different. Because I am 100% certain the tachometer does not read the same in 5th gear + lockup cruising on level ground. It is hard to gauge the lower gears unless you REALLY pay attention to lockup, or unless I drove with a scan tool... but even then, there is no lockup in 1st. I know the diesel will lock up from 2nd gear on. Not sure about the gas.

My gut feeling from driving the cars tells me that just the final drive is lower on the gasser. And if that is indeed the case, any gear ratio monitoring won't be bothered by the change. I know you can put a gasser 01M behind an ALH and they work just fine. They just spin the engine faster. No faults, no strange shifting, nothing. But the 01M is a totally different unit.

I could always swap the converter and valve body from the GMR trans if that would be helpful, I suppose. I put a new converter in it about 130k miles ago.
 
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oilhammer

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outside St Louis, MO
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There are just too many to list....
I think its group 015 in engine measuring blocks that outputs wheel speed, log that and engine RPM, back calculate it. I'm sure the gasser has similar measuring blocks. If they're the same, it'll be obvious.

I already know that much, I'm just trying to determine where the difference is.

I'll know more by this weekend.
 

Mikkijayne

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The 2.727 may be the rear diff ratio for the FLA..
I didn't quote diff ratios as the information in Elsawin didn't make a great deal of sense. It had 2.727 and 3.09something for the diff in the trans, but the usual 3.889 and 4.111 for the rear end. I have to assume on that basis that the output gear set which drives the front end is correcting the ratio for the front so that the wheel speed is the same at both ends. Since I couldn't find specifics for the FAL or GMR I couldn't say whether they are the same or not.
 

DeliveryValve

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Western US
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Passat GLS Wagon
What this thread needs is Pictures!



On another note, I guess I have too much time on my hands today. In a round about way of researching and connecting these sources below together.

http://pics.tdiclub.com/data/500/3_transmission.pdf
http://pics.tdiclub.com/data/500/zf_parts_catalog_pdf.pdf
http://pics.tdiclub.com/data/500/5HP19FLA.pdf
http://forums.tdiclub.com/showthread.php?p=4151856

I conclude the transmission code of a 1.8L 4 motion is FAL and has a differential gear ratio of 3.73. All other gear ratios are the same as the GMR.


.
 

oilhammer

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outside St Louis, MO
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There are just too many to list....
Yes, I am thinking that it would make the most sense that they'd simply do what most other VAG slushboxes do (regardless of the manufacturer) and just run a different final drive and leave everything else the same.

Manuals, of course, are a very different story. And they've always been that way.

Not much for pictures yet. Here is the wrecked donor car right before I lifted on to the trailer:



Same color as my 2004 TDI sedan, so I saved the rear bumper cover and sideview mirrors. :D

Here is the engine/trans out of that car, but that is not the engine I am going to use:



That engine/trans went into their other 2005 Passat that has 270k miles on it. I am using the engine I took out of that car. It is in good working order however. And the GMR transmission works fine, and I installed a new converter in it about 130k miles ago. If I don't end up needing/using it, I may be selling it or perhaps scouting around for a B5 TDI with a bad trans.

Really a shame as that sedan pictured above only had 98k miles on it and was otherwise perfect. But it was smacked HARD sideways in the left front, knocked both unibody rails over a couple inches, blew both front airbags, completely smashed the PS fluid reservoir, intercooler, washer bottle, coolant bottle, etc. Customer also wanted the ABS assembly for their other car, as it had a bad one. I didn't think I was going to be able to get the ABS unit out of the wreck since the body was literally wrapped around it but with some patience, a prybar, and a Sawzall, I was able to rescue it.

That car has so far already given up its CCM and harness, its horns, the driver door window switch, its antenna, its radio, and a caliper, to various other B5s in need. So at least it wasn't a total loss, and if I can make my gasser into a TDI, a few more parts will live on.
 
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