Hard shift

[fmster]

When the tranny is cool in the car right after the car warm up,the trany shifts firm and hard chirping 1,2 but after it's hot it shifts smooth why?

 

[McHaggis]

Others with more knowledge will chip in with their thoughts I'm sure but from the little I know I would suspect your pump has too much clearance. This causes good oil pressure when it's cold but the extra clearances allow bypass so the pressure drops when the oil gets hot. A pressure check will confirm if this is the case.

The following has been copied from a thread by WE4.... (I hope this is OK Bruce? LOL) For the full version... http://www.turbobuick.com/forums/tr...ttention-new-version-strengthening-2004r.html Well worth reading!

"Wash in hot water and dish soap and compressed air dry and set aside. The Chrome Moly ring kits have been known to be a little rough too. We wet sand with 600 over glass in solvent the flat edges and then fine wire wheel the circumferance. It is imperitive that the pump rotor and slide are measured very carefully. They MUST be within .002 of the pump cavity depth.
Too loose and line pressure will be low hot, and too tight, rotor and slide could bind, and break rotor, slide,converter neck,or all the forementioned parts. We set them .0013 in the hole, or in the "pocket". The way this is done is, the face is cut, or surfaced. Then another tool bit comes in and with the premeasured rotor and slide thickness', cuts it to .0013 clearence. This is VERY IMPORTANT!!!!!! ."

 

[SSedan64]

I agree ^^^. Best way to diagnose is with a pressure gauge. Port is just above shift shaft on driver side.
If it's only the 1-2 shift that's smooth it may be Servo or internal seals leaking pressure when hot.

 

[turbo nasty]

PSI test x3

 

[fmster]

Thanks fellas for the good info.