NV4500 5 speed makes a heck of a rattle when upshifting and accelerating. Quiets down when speed stabilizes. Rattle is louder when the truck is under a load (like hauling the camper).

Dealer says this is normal and is a bearing noise from the clutch. No worries!???

Guess I'd like some reassurance before I totally buy into this explanation. 3900 miles on the truck. '04 CCLB 6.0L 4x4.

Thanks :help2:

Update. Wendt back to dealer. Not bearing related, but just gear noise from the trans. No probs according to dealer. I will try diff fluid to quiet it down some, but they weren't willing to do anything more.

In 1997 or 1998 GM went back to using a solid mass flywheel with the NV4500 with a dampener in the trans tail-housing. This does create more gear rattle at low speeds and heavy load or under low throttle applications while unloaded. Athough, it is while you are shifting so you could be hearing some clunking when you let off the throttle.

Edit: Wait, you have a gasser so you would have a SMF no matter what. Plus on a gasser you tend to have less gear rattle than a diesel and there is no dampener in the trans. I would still imagine you would hear some gear rattle though even with a gasser.

i have 96 4x4 6.5 5 spd with the dual mass flywheel it makes noise when its cold and when shuting it off it sound like the crank is going to fall out of it. the tranny as been check but the fly wheel was not changed out. you can put a soild fly wheel in but it shift harder.