HI: I have an'07 Aspen with 50K miles on it and when I go over a small bump, at very low speeds (10mi/hr), I get a faint tin type "bong" sound(Like hitting a steel drum with a rubber mallet). from the rear end. It doesn't happen if I go over a bump fast(> 20mi/hr). Seems to only happen at a crawrl speed. This happens going straight and when turning. I took it to the dealer and they replaced the rear shocks but this did not cure the problem. Any thoughts ?

 

Could be a lot of things. Check to make sure it's not something inside the truck first -- make sure the jack, etc. to change the spare is secure, and that there's nothing metal banging around in the compartment behind the 3rd row. It would also be worth crawling underneath and pushing/pulling on shields, the muffler, etc. Something could simply be loose.

 

i have the exact same noise in my wifes aspen, i still have not found the source but it defiantly is coming from the rear suspension, i can hear the noise if i rock the car side to side but not if i jump up and down on the hitch, any help would be greatly appreciated

 

My first instinct would have been the shocks, since the oem shocks are such crap, but since they already put new ones in, that rules that out.

By the way you describe the noise, I wonder if your spare isn't tightly drawn up against the bottom of the truck, or needs air in it. At speed, it may be held back so that it pulls the cable taught, while at low speed it might be dangling loose just enough to bounce against the bottom of the truck and make a noise. It's easy enough to eliminate this as a possible cause by tightening the spare wheel winch until it clicks (you can't overtighten it, so no worries there). Check the pressure on the spare before you tighten it, too, so it'll be good and snug.

 

i know this post is fairly old but i figures i would share my knowledge, my father in-law and i crawled under my wife's 2007 aspen because it had the same noise that you are describing and we cam to the conclusion it is the upper spring isolautor which is a dealer part only but run about $12 each which isn't bad hope this helps!