A4S 310R manual valve seal repaired

[billb]

It's been a busy summer, and in August I noticed the E34 had a growing puddle under it. The main tranny pan looked quite damp, and there were drips visible along the manual valve arm. I pulled her in the garage, where she's been since then. Over the past few weekends I spent some time pulling off the pan and seeking leak repair. Steps I took (no pictures, but descriptions follow) are below.


Drained main pan.
Removed the main pan.
Replaced the filter.
Disconnected the manual valve linkage.
Disconnected the shifter detent spring (2 bolts).
Drove out the roll pin connecting the manual valve shaft and detent arm.
Pulled out the roll pin holding the manual valve shaft in position in the trans body.
Pushed the manual valve shaft into the transmission housing (there is a clearance hole in there)
Used a curved screwdriver blade (modified to curve of oil seal recess) to pry old oil seal out.
Inserted new oil seal using 14mm socket and prybar.
Applied trans fluid to oil seal ID
Slid manual valve shaft back out.
Reinserted roll pin holding manual valve shaft in position.
Reinserted roll pin holding manul valve shaft and detent arm.
Reconnected the shifter detent.
Replaced the main pan gasket.
Reattached pan in linear fashion (not cross-tightening pan) with torque wrench.
Installed and torqued drain plug, with new crush washer.
Reattached manual valve linkage and hooked to cable.
Refilled transmission as best I could cold until fluid ran out of fill hole.
Got car to level ground, refilled to full.
Ran car at idle in all gears until fluid was warmed, and continually monitored level.



Drove it up to fill up with gas, then we put another 40 miles on it over the course of the day. At the end of the day, it was drip free. Will continue to monitor. Smoothest its shifted in years so far.

[genphreak]

Bill,

Thanks for taking the time to share. A brilliant write up and easy to read solution for anyone running the GM GM 4L30-E/A4S-310R. Certainly something many of us will need at some point.

1. Why do you tighten the pan bolts from one side to the other instead of criss-crossing?
2. Do you know if this problem happens (and might the fix be similar) for ZF 4HP/5HP transmissions too?

Cheers!

[billb]

Hi Genphreak-
I read in another location that tightening in this fashion would help prevent leaks. This is a very thin gasket, and I'm inclined to believe torquing it linearly around the pan will prevent gaps between bolts. Very low torque setting too, like 12Nm.

Here's the link to where I got my info on the pan. I understand it's for an aluminum pan, and this is a steel pan, but it seemed logical.
http://forum.roadfly.com/threads/13182117-Oil-leaking-maybe-out-of-Transmission-Breather-on-top-of-Auto-Transmission-2000-528i

2. I'm not sure on the ZF boxes, but anywhere there's a seal is a leak potential. Mind you, this car is a 5/94 build, and to my knowledge, this is its 4th transmission service in 188k miles. (documented at 61k, 92k, 140k, and just now at 189k).

Just driving it again these past 2 days has me thinking about keeping it around a while longer. Needs thrust arm bushings and rotate/balance again, but knock wood, she's still a good old girl.

[billb]

After 200 miles, I crawled under it tonight. Dry as a bone from the transmission. cheers

[RobPatt]

Hi, I have the same transmission, and a leak.

what is the manual valve arm?

[billb]

Rob-
It's the thing the shifter cable is attached to. It's on the outside of the transmission.