Reverse hesitation after sitting for 2 days

[Russell]

I had, for the first time, a reverse hesitation (did not seem to engage)when I first backed it out of the garage after not driving it for two days. As I usually drive it daily, I haven't really noticed the problem even though I had suspected a slight hesitation before. It seems ok now after staring and moving the car.

Per the archives, it could be the dreaded GM transmission failure or somehting else. Any advice? I had it completely serviced about 13,000 miles ago at 82,000miles, I think for the first time.

[Russell]

Not sure, if anything to do at this point. Is it "broke enough" to even check out? Should I take it to one of the following for an analysis: dealer, independent shop, or a transmission speciality shop? My guess is start with my independent shop.

What are my options if I need to repair/replace? local rebuild, replace with BMW factory rebuild, or swap with used transmission? Seems as if all options have good points.

BTW, I have heard that the GM tranny is easy to fix and I have heard they are tricky to fix??

Just looking for advice. The tranny may last many more years with no problems except with the slow reverse engagement after sitting several days.

I had, for the first time, a reverse hesitation (did not seem to engage)when I first backed it out of the garage after not driving it for two days. As I usually drive it daily, I haven't really noticed the problem even though I had suspected a slight hesitation before. It seems ok now after staring and moving the car.

Per the archives, it could be the dreaded GM transmission failure or somehting else. Any advice? I had it completely serviced about 13,000 miles ago at 82,000miles, I think for the first time.

[Russell]

I now know this a common issue. Dealer even has a TSB on the problem, It is not broke enough to fix (could last a long time) and does not require a complete rebuild. Looks like an independent tranny shop can handle the repair. I would not know these things without the members of this board.

Thanks,

Not sure, if anything to do at this point. Is it "broke enough" to even check out? Should I take it to one of the following for an analysis: dealer, independent shop, or a transmission speciality shop? My guess is start with my independent shop.

What are my options if I need to repair/replace? local rebuild, replace with BMW factory rebuild, or swap with used transmission? Seems as if all options have good points.

BTW, I have heard that the GM tranny is easy to fix and I have heard they are tricky to fix??

Just looking for advice. The tranny may last many more years with no problems except with the slow reverse engagement after sitting several days.

[sbcncsu]

I now know this a common issue. Dealer even has a TSB on the problem, It is not broke enough to fix (could last a long time) and does not require a complete rebuild. Looks like an independent tranny shop can handle the repair. I would not know these things without the members of this board.

Thanks,

Knowing what I know now, I would have just performed the repair. The only real bad part is that, in my case, pieces of the offending gasket ended up in the recesses of the transmission, however, none got lodged in the valve body though so shifting never really suffered.

In my case, the frictions and steels of the internal clutches, the bushinges, the seals, everything inside the transmission was in great shape at 140K miles. It didn't need the rebuild, it was fine except for the offending gaskets.

[Unregistered]

Mine has been doing it for about 2 years now(I only drive it on weekends). I recall seeing something about a board frequenter named Kurt who specializes in these trans.

Charlie in Jax FL
95 525 Auto 94k

[ryan roopnarine]

i take it that you've read the TSB about this subject? scott c sez-paraphr---that if your internals are OK, you just need the seals done (which requires less work than a rebuild)

http://plaza.ufl.edu/rroopnar/SI%20%...pter%20Cas.PDF

[Russell]

Looks like a dealer only repair to me. It also looks like a design problem. Wonder if a good tranny shop can do teh repair?

Thanks for pointing out the TSB

I am sort of worried now.

i take it that you've read the TSB about this subject? scott c sez-paraphr---that if your internals are OK, you just need the seals done (which requires less work than a rebuild)

http://plaza.ufl.edu/rroopnar/SI%20%...pter%20Cas.PDF

[sbcncsu]

Looks like a dealer only repair to me. It also looks like a design problem. Wonder if a good tranny shop can do teh repair?

Thanks for pointing out the TSB

I am sort of worried now.

I tackled this problem on my 1995 525iA. It was slipping when cold in reverse and began leaking. The problem is this gasket:


It is not durable enough nor is it clamped with enough force to prevent it from deforming as you see in that picture.

The gaskets seals the fluid pressure from the pump back to the clutch packs. Once the gasket goes, you have lower hydraulic pressure and thus, the slipping trans.

This is the housing that it seals, it is the overdrive housing. It is forward of the main transmission housing:



When the gasket gets really bad, the trans begins to leak a little ATF where the main and overdrive housings join.

The good part is that this repair CAN be performed by a qualified transmission repair shop. DO NOT LET THEM TALK YOU INTO A REBUILD if all you are experiencing is the slipping when cold. If it slips when warm or shifts really badly, then rebuild it.

I recommend that you take a copy of the service bulletin above with you to the shop. If possible, go the the stealer and get the repair kit associated with the service bulletin.

If you buy parts from an aftermarket supplier like ATC or Transstar Industries, you will not get the revised (read STRONGER) bolts that will increase the clamping force when assembled.

HTH. Any questions, PM or e-mail.

EDIT: Cost for me was an aftermarket rebuild kit at $135. The kit from the dealer should be around that, perhaps slightly more. The time for a good trans guy to do the repair should be on the order of 4 hours R&R, 4 Hours Repair, so 8 hours at ~$50/hr. Count on $400 + parts and shop supplies.

[ryan roopnarine]

scott,.....so if a tranny shop rebuilt this transmission around 2002 or so, there's no guarantee that this won't happen? I thought that this would be addressed in a rebuild kit by that time. I suppose if changing fluid frequently (at every oil change) won't prevent this from happening to me, I'm going to start slacking off more.

I tackled this problem on my 1995 525iA. It was slipping when cold in reverse and began leaking. The problem is this gasket:


It is not durable enough nor is it clamped with enough force to prevent it from deforming as you see in that picture.

The gaskets seals the fluid pressure from the pump back to the clutch packs. Once the gasket goes, you have lower hydraulic pressure and thus, the slipping trans.

This is the housing that it seals, it is the overdrive housing. It is forward of the main transmission housing:



When the gasket gets really bad, the trans begins to leak a little ATF where the main and overdrive housings join.

The good part is that this repair CAN be performed by a qualified transmission repair shop. DO NOT LET THEM TALK YOU INTO A REBUILD if all you are experiencing is the slipping when cold. If it slips when warm or shifts really badly, then rebuild it.

I recommend that you take a copy of the service bulletin above with you to the shop. If possible, go the the stealer and get the repair kit associated with the service bulletin.

If you buy parts from an aftermarket supplier like ATC or Transstar Industries, you will not get the revised (read STRONGER) bolts that will increase the clamping force when assembled.

HTH. Any questions, PM or e-mail.

EDIT: Cost for me was an aftermarket rebuild kit at $135. The kit from the dealer should be around that, perhaps slightly more. The time for a good trans guy to do the repair should be on the order of 4 hours R&R, 4 Hours Repair, so 8 hours at ~$50/hr. Count on $400 + parts and shop supplies.

[sbcncsu]

scott,.....so if a tranny shop rebuilt this transmission around 2002 or so, there's no guarantee that this won't happen? I thought that this would be addressed in a rebuild kit by that time. I suppose if changing fluid frequently (at every oil change) won't prevent this from happening to me, I'm going to start slacking off more.

Chances are the new bolts weren't installed. That isn't that big of a deal. The new gaskets (aftermarket) are better and shouldn't become brittle like the OEM. Another benefit is the rebuilder probably had an updated torque specification.