I have a 2006 Silverado 5.3 Crew Cab with 39K miles. When I am accelerating at a normal rate, I am getting what seems like a slight delay going from 1st to 2nd, then when it shifts sometimes it clunks and it is a rough shift with a small jerk. I do not have this problem with any of the other gears, it is a very smooth shift. If I get on it, the it is delayed even further then the shift is real rough. Any thoughts?

 

sounds like the shift solenoid is going bad. had a like issue with my trans when the truck was new. dealer replaced, and all good..

good luck

 

same thing happened to my 97 half ton. try the solenoid first. it's a pretty common problem from what i've heard. my problem ended up being the torque converter though

 

are you the original owner?
If it shifts hard like that,
the truck may have a quick-shift kit like mine.
it just helps it go to the next gear and get up to speed faster or whatever.