Vlaudi

I had a problem in my A4(1997, 5 speed), automatic transmission. The shift lever do not go in parking position.DaveInSaltlake had give me same tips, an year ago, but i cannot find it.
I think that the problem is the selector register, a plastic piston inside the valve body, but I do not find this part in the parts catalog at the dealer.
Thanks
VLaudi

shawfm

<ul><li><a href="https://forums.audiworld.com/a4/msgs/2730534.phtml">searched using Automatic and your user ID as a filter</a></li></ul>

DaveInSaltLake

but if you haven't tried to adjust the cable first I'd strongly recommend that. and...unless you've had the valve body out of the tranny I don't see any way this piston could get damaged.<ul><li><a href="http://www.zf-group.com/pdf/5HP19FLA.pdf">http://www.zf-group.com/pdf/5HP19FLA.pdf</a</li></ul>

Vlaudi

I removed the shifter and the cable, and did a complete inspection and lubrification.The cable was adjusted and installed. The filter and fluid was changed (original Audi fluid).
Everything works fine while it´s cold. When the transmission is hot (after driving for about 45 minutes, the shifter is very hard to move. This week,the worst hapens! after I try to move the shifter, it became soft for the positions, R, D, 4,3 and 2, and impossible to move to P. The problem is that the car do not move, when you put the shift in P or R. I used the VAGcom, and scan/checked that what is selected from the shift match with what is indicated in the VAG.Not wrong was found!Dave thaks for your help!

DaveInSaltLake

have you gotten an opinion from a good independendent Audi mechanic?

Vlaudi

Audi mechanic ! Yes, he sad that could be the shift cable, but as I told, I checked the cable.What is really funny, is that the problem only happened when the engine/transmission was warn/hot.About the plastic piston, the number 50.020, is that the part number ?
About the valve assy. It is possible to repair it (in case of problem) or it need to be changed complete by another new ?

Regards

DaveInSaltLake

no, that's not the part number. if you look through the pdf file you'll find the ZF part number for the piston. ZF is the company that manufactures the transmission.

has your transmission ever been taken apart?

the valve body is not that difficult to remove. drop the pan, remove the filter, and unscrew 20-something bolts to drop the valve body. at that point one can change out the plastic piston that was my problem.

sounds like it's time for a 2nd opinion from another good mechanic.

if your first guy is that certain it's the cable or adjustment why don't you see if he'll guarantee his work? if it fixes the problem you happily pay....if not, he happily admits he was wrong and tears up the bill.

Vlaudi

Dave, the transmission were never been taken apart.The car and the transmission are with only 35,000 miles.
I really beleive that is the plastic piston, that may be disengaged from the axle that connects the shift cable or became deformed.I do not understand why the piston is made of plastic (may be to reduce friction with the aluminum valve body).I got the ZF parts catalog that you send in annex(very nice), and I have a question.
Do you have the ZF Repair manual for this transmission and/or valve?
If not, where did you got this part catalog?May be I can try to get the repair manual!
Once again Thank You very much for your time and attention!

Regards
Vlaudi

DaveInSaltLake

rebuilding this transmission.

I looked over my plastic piston and it is damaged. I'd be happy to send it to you if you think it would help.

I found the ZF parts manual using Google.

Vlaudi

Ok Dave !

I will look on Bentley (I have one copy). If I found the solution, I will post it here and inform you.

Thank You for your support!

Take care!

Vlaudi