4R100 shifting problems

Reply Subscribe

Thread Tools

Search this Thread

Aug 28, 2005 | 09:22 PM

017.3

Thread Starter

Freshman User

Joined: Nov 2004

Posts: 30

Likes: 0

4R100 shifting problems

I have a 2001 psd f-350 and it started to not shift correctly. It wouldn't shift out of first while under acceleration, but if you let off it would shift fine. The low clutches were black the intermediate friction clutches were gone and my drive and o/d clutches were black also. It was also running hot 200-300 deg for obvious reasons. So i rebuilt my tranny and put in a transgo tugger kit and a .427" pressure modulater in it. Now it doesn't want to shift until it almost redlines the motor then when it does shift it doesn't know what to do. it feels like it goes from 1st to drive then downshifts back to 2nd and if you accelerate to much it will downshift back into first at redline rpm's and start the shifting process all over. If i shift it manually it does fine until i put it back in drive. any help would be appriciated. I reset my computer after i rebuilt it, also my o/d light still flashes sometimes.

Aug 29, 2005 | 08:05 AM

Casey

Posting Guru

Joined: Jul 2003

Posts: 2,210

Likes: 2

Did you replace the mechanical diode with the sprag type one way clutch? The mechanical diode was most likely the source of the original failure. If it's still in there it needs to come out.