2004 4wd crew cab suspension

[Username123]

My 2004 4wd crew cab has 37k miles and though I like this truck, the quality of ride continues to disappoint (and I'm pretty easy to satisfy). At 40 mph, the rhythmic shuddering starts. Got tires and suspension checked at dealer at 8k/15k/30k--no identifiable problem. One day noticed that the inside of the front tires (OEM) were severely 'cupped' or scalloped. Got new tires of different manufacturer installed two weeks ago--problem even seems worse now. Heard somewhere that this was a suspension/spring problem flaw in the new crew cab and GMC wasn't able to respond to it.

 

Thanks in advance.

[lerbud]

check your air pressure. let it down to about 35 psi all the way around if you are not hauling anything. i bet you will notice a big difference.