Originally Posted by
L_U_C_K
I have a question.
When the Suburban sits for a bit, I start it up and give it a minute to run. When driving, it stays at high RPM from 1st to 2nd then clunks into second. also, 2nd into third but not as bad of a clunk.
Now when it warms, it is not that bad. it seems to shift smoother and no real bad clunk.
The transmission has 30k on it, but the truck has not really been driven for about 3 years.
Could this just be a common thing,
could it be torque converter,
Or could it just be because it is cold??
Start with the fluids as others suggested, if that doesn't fix it, it may be the vacuum diaphragm on the side of the transmission. It's on the passenger side...inspect it for damaged hoses (cracked and or dry rot)..
I'd drop the pan and do a filter if/ when changing the trans fluid especially if it's service is an unknown.