What Would Cause Transmission To Seemingly Stop Shifting Properly When It Warms Up

Published 07/26/2019

Question:

would a transmission oil cooler help

asked by: CHARLES B

Expert Reply:

I've had similar issues with cars and the problem wasn't that the temperature of the fluid was causing the change in shifting/performance the issue was that the fluid filter was getting clogged with debris (from clutches etc. failing and coming apart in the transmission) and therefore not able to allow the transmission to shift properly. Once you park the car the debris falls off of the filter and it appears to shift normal again till it clogs again.

The solution is to take the vehicle to a transmission shop and see if they can replace the damaged components before the whole transmission goes out. I'd be willing to bed that if you drop the pan (the first thing a shop will do) you'll find that it's full of debris.

In the two situations I had where this happened the torque converter failed and caused the problem.

expert reply by: Jameson C