Shifting question

[Mr. BILL]

My son's '90 525 iA is demonstrating a shifting problem. When cold, if doesn't want to shift out of first. After a few minutes of warm up, if you back off the throttle at the point it should shift, it will go into 2nd. Once it completely warms up, it seems to work fine.

I checked fluid level, if anything, it's a little high. The tranny was rebuilt about 10K ago. Could it be a linkage problem?

Thanks in advance

[uberhahn]

If it was a linkage problem, it wouldn't be temperature dependant.
Did it shift like this before the "rebuild"?

To me, it seems more a question of what fluid the transmisison was filled with.

It is normal for cold shifts to be "stiff", but not the extent you describe. If possible, find out what the trans was filled with. Better yet, take it back to the the shop that did the work and ask them to drain and refill with Redline MTL.

My 2.3345 cents. I'm sure others will chime in.

uberhahn

[uberhahn]

Sorry,

just realized your son's car is an Auto. I'm gettin' old.

[gale]

Not totally unusual in colder weather. A full synthetic fluid change will help. I believe it has the ZF 4hp22 trans & they respond very favorably to fresh fluid changes, especially with full synthetic. Do a few drain & fills about 50 miles apart with an inexpensive Dexron III & then do 2 more drain & fills with Amsoil or Redline or Mobil 1 full synthetic ATF -- you'll notice a marked improvement if there isn't some other more serious electro-mechanical issue going on. Even tho it has been recently rebuilt, perhaps there is some crud in the valve body left from its former mishap.

Google for more details on the electrical side. Maybe there's a temp sensor that needs replacing. If you can locate the spec & a schematic, you can measure the resistance of the temp sensor via the plug on the TCU connector.