99 silverado tranny

[dabaer]

hi there, a friend of mine has a 99 silverado with 143000 miles, its got an auto tranny. Last summer it started to shift hard between first and 2nd gear. It does it mostly when the truck is cold in the morning but once it warms up to running temps it shifts fine. now that the temps have started to drop it is not acting up as much compared to the summer. But now he is thinking he should get a rebuild. I was just wondering if anyone has an idea of what could be going bad, and if he needs to get the rebuild.

thanks

[deadeye]

There could be a shift solenoid thats broken. Thats a pretty common problem. Otherwise changing the fluid and filter would be a good place to start and you would be able to see if there is a bad solenoid.

[jeffreyd]

with that much time on it, i would check carrier bearing and u joints also

[dabaer]

he already changed the fluid and filter.

deadeye

if the solenoid is bad, would it still go into the gears, and wouldnt it get a check engine light?

[deadeye]

It should. That doesn't mean that it will. When I pulled the pan on my blazer to change the fluid I was greeted by a solenoid with the connector broken off hanging from a wire. It didn't throw a code but definitely shifted weird. I asked the transmission shop about that when I got the part from them and they said it was a common problem. Im still not sure how it would be like that and still function but thats what they told me. I honostly try to keep my nose out of transmissions if I can. Its more stuff going on than I care to deal with.

Im hoping airjer will chime in with more info since hes the true pro.

[dabaer]

deadeye, thanks for the info.

very true...too much goin on for me too!

[Scott K]

When removing the pan, there isnt much clearance between the pan and the cross pipe, and the pan can knock off or break off the connector to the solenoid. This is a common comeback repair from a lot of shops.