2011 Touareg TDI A/T Valve Body Part#

[MP517PRCT]

Thank you for sharing your knowledge, oilhammer!

I'm guessing then, it doesn't matter if the replacement transmission is of the same "code" as the original so long as it is the correct part number (0C8300036Q)? Mine is a "MHC" and I found several "MHN" transmissions.

 

[oilhammer]

No, you'll want the same 3-digit code.

And the part number is NOT the same.

MHC:

0C8-300-037-F (new) or -036-FX (reman) or -036-PX (reman)

MHN:

0C8-300-036-Q (new) or -036-QX (reman)

 

[MP517PRCT]

Damn, I knew it wouldn't be that easy...

 

[oilhammer]

Looks like a reman unit from the dealer is just shy of $5k. You may also ask around if someone can rebuild it for you. It is the Aisin TR80SD unit, which aside from the case and such, should use mostly the same basic internal architecture as any other modern 6 or 8 speed longitudinal Aisin automatic. I know the valve body itself looks the same as something you might find in a Tundra.

 

[TurboABA]

Well, that didn't work...

I replaced the valve body, and no change.

So you swapped in a whole known working valve body and solenoids? Or you transferred your solenoids over? Or??????

 

[MP517PRCT]

So you swapped in a whole known working valve body and solenoids? Or you transferred your solenoids over? Or??????

I swapped the whole valve body unit.

 

[TurboABA]

..... which had been bench tested and verified as properly working before the swap?

 

[MP517PRCT]

Yes, at least according to the company that I purchased it off of.

 

[MP517PRCT]

Took the T-Reg to a transmission specialist yesterday. The downside was that he doesn't work on VWs (except Routans, because they have Chrysler transmissions). Even though he doesn't work on VWs, the owner took about 30 minutes of his time, hooked his scan tool up to the T-Reg and took it for a test drive with me. Seems like the problems with the Pressure Solenoids and Output Speed Sensor are both intermittent, as he got voltage/signal from both, although the graph showed that something is wrong with the Pressure Solenoid. He also thinks that the primary clutch is leaking/has blow-by, since it requires a bit of throttle to get going (this explains the PO saying that the transmission was "slipping in 1st gear.")

Anyway long story short, his advice was get a transmission from a salvage yard and replace the whole unit myself. I do have access to a garage with a lift at work (I am going to make sure they have a transmission jack as well), so I am now leaning in this direction. I located a transmission ($800) with the correct code and I'll be ordering that tomorrow. Besides replacing the ATF/filter/pan gasket, is there anything else that I should be replacing with I am in there? Also, any special tools besides the normal triple squares and torque wrenches that I'm going to need?

 

[TurboABA]

If the problems are "intermittent", I'd consider paying a dealer to diagnose the wiring harness (unless you have the knowledge\ability to do it yourself) before I went through all that hassle to swap out the tranny. With the proper tools, oscilloscope, etc. a good tech should be able to isolate the problem before you throw any more parts at the Touareg.

 

[MP517PRCT]

After multiple rejections, I found a local, independent VW shop to look at it. It's scheduled for service 8/2, so we shall see...

 

[MP517PRCT]

Got a call from the shop yesterday, they had a Q7 in a few weeks ago with nearly identical faults. Replacing the transmission wiring harness fixed the problem with that one, so we are going to try replacing the harness on mine. Fingers crossed, it does the trick!

 

[MP517PRCT]

The VW specialist pin tested the harness and couldn't find anything wrong with it. They referred me to a transmission specialist that does work on VWs. Had the Touareg towed there. The owner of the transmission shop checked with the VW dealer across the street, and he thinks that the TCM needs to be reprogrammed. He is going to take it across the street and have the dealership try to reprogram it.

That's the latest on the saga of the T-Reg...

 

[MP517PRCT]

Well, the reprogramming didn't work. Transmission shop says it's cheaper to get a transmission out of a salvage yard, than it is to rebuild. Guess I'm in the market for a used unit.

 

[TurboABA]

Damn....

 

[MP517PRCT]

Got a used transmission with 110k miles on it for $1140 shipped. My Touareg has 118k, so it's pretty close mileage wise. The shop that is going to do the replacement quoted me $1800 to swap, flush, fill, and reprogram the new transmission. Looks like I'm sitting at $3000 for the replacement. Considering I paid $9000 for the T-Reg, I'll have $12k into it. Looking at comparable T-Regs for sale on Auto Trader ($14k to $15k), I'll still $2000 to $3000 to the good! Fingers crossed this fixes it.

 

[MP517PRCT]

Well, finally after three shops, a salvage yard transmission, two used valve bodies, and one trip to the dealership, the Touareg is finally fixed. Yes, this all started in April of last year!

Dealership replaced the valve body with a new unit, that didn't fix it, but the tech line suggested replacing the TCM. Sure enough, that was the problem all along. Cost me quite a bit of coin, but at least it's fixed.

2011 Touareg with 116k miles = $9000
Salvage yard transmission = $1100
Installation at transmission shop $1900
New valve body & TCM at dealer - $5500

Right now, I'm sitting at $17,500 and a quick check of Autotrader listings has similar age/mileage Touaregs listed between $16,777 and $19,500 so while my gamble didn't pay off, but I didn't lose my shirt either.