Hard shifting tranny

Sep 14, 2006 2 Replies

I recently bought a used 95 GMC Sonoma extended cab pickup truck (4 X



4). I have noticed that after driving it and warming everything up that the transmission shifts hard between 1st & 2nd gears. I have noticed the fluid is a little overfull and appears dirty. Does any one think a dirty filter is the cause of the hard shift. Or is there an accessible part that can be replaced when I have the pan off to change the filter that is obviously the cause. It also has the 4.3 vortec. Auto transmission and A/C.

Dirty filter affects line pressure / could cause hard shifting. Worn trans fluid [ thermal breakdown ] could do the same. Trans service is cheap insurance against rans failure.

Thanks Paul,

You confirmed my suspiscions. I changed the filter and fluid today, I also added a quart of slick 50 tranny treatment. I've driven it twice today. The first time there was an immediate improvement. The second time was even better. I suspect the new filter is cleaning the remaining fluid in the torque converter.

Join the Discussion

Have something to add? Share your thoughts — no account required.

Didn't find your answer?

Ask the community — no account required