So I don't know if I've seen anything posted like this, but I figure maybe it's worth a shot. I was hoping it was a CV shaft, but I don't believe it is. The issue is that when you let off the gas, mostly in town driving, I hear a clunk if you will. Then when you pick up the gas you'll hear it again. It reminds me of slack in a differential and it makes contact on the deceleration and acceleration. If that makes sense? It sounds like it's coming from the passenger side. I jacked it up today and it seems as the slack is inside the transmission, as I saw or felt no slack in the shaft itself. I guess I should see if I can locate a print/schematic for the trans to see what's inside that could be an issue. I'm afraid I'm going to break something!

I also get what feels like a hesitation. Almost like it's missing, but no check engine light, so I assume it's not. I really only notice it when I start up a hill or grade, but if it kicks down it goes away. I'm not sure but was thinking like a lockup solenoid or something, but possibly a pressure related thing since it seems they have some pressure module issues or something like that. I'll have to read up more on that I guess. Maybe I'll answer my own questions lol

anyhow thanks for listening

 

Hi 204copper, welcome to the forum. I had a clunk like you describe in my 2001 Impala. It drove me nuts in finding it. I eventually stumbled on it and it turned out to be a bad motor mount. How are your's looking? On the stumbling on a load up a hill, that same Impala had the same problem. I first changed my fuel filter, which did not solve it, then someone suggested checking the fuel pressure regulator. I went through the service manual I have and put a pressure gauge on the fuel rail, sure enough it was low. I also had a bad fuel pressure regulator on my 2002 Tahoe.

 

I haven't gotten a chance to look at all of them, but if you rev up the motor in park I get no real movement. I'm gonna look harder at it tomorrow though. I can't do the fuel filter as it's in the tank and only comes on the pump apparently. Another brilliant idea from chevy, but better than none at all!