'94 Z28 auto:
Won't go into forward gears until rpm's held at 1600 or above. (Clunks in abruptly) Once engaged it shifts/drives normally, always goes into reverse normally, no weird noises in any gears forward or reverse, no slipping, etc. Once taken out of drive(placed in P or neutral), must rev up again to get it to re-engage. Full of fluid, fluid is nice and clean/doesn't smell burnt.Any ideas?
Thanks very much,
Rick

 

Cracked forward piston, most likely. Try putting in manual "1" position and "see" if this helps get a better forward clutch engagement.

 

Thanks Dana,
I have read it could be forward piston, or forward roller clutch. it acts the same regardless of shifter orientation. Once forward locks in it will drive normally, spin tires etc... Engages reverse immediatly, but must rev it up to get the forwards to engage. Was hoping it is a solenoid or something easy like clogged/warped/damaged filter. Have a buddy bringing me his pressure gauge tomorrow....
Rick

 

Good idea....

 

Hey Dana,
This forward piston you speak of...is it the one in the valve body? If so, can it be replaced without removing the valve body? And do you sell 'em individually or will I need additional parts?
Thanks,
Rick

 

You are talking about the forward accumulator piston. I do not see this being the problem you are describing. The forward piston I am talking about is in the input drum. The 1993-1996 units had these and they would crack once in awhile. In the 700R4's this never happened. Once you have it apart you will be able to see what went wrong. Then you can replace the aluminum pistons with the steel molded rubber type.