my CTD: quad cab, 4x4, 2500, OR pkg, all bone stock. 15k miles. 52 psi front, 56 psi rear, mostly empty driving. use the quad cab & 4wd on the beach, more than I use the Diesel's towing ability.

grumbled like crazy from 55~60 when new, then I towed with it, or did something, then it vibe'd and growled from 60-65 for a few months

last week, had just axles & T-case fluid changed, now it vibe's and rumbles & resonates from 70~75, and horribly above 85 (passing some folks - lost track of speed - till the roaring started)

so is Motor Trend right, are our trucks really civilian versions of dump trucks?

don't GM use the same AAM axles in the DMAX? are they having this problem?

 

GM uses GM axles in thier D maxes.. 14 bolt rear, and probably a Dana 60 front.. Sorry to hear about your problems.. Guess I should count my lucky stars that I don't have these issues.
Scott

 

Make sure yours has the UPDATED powersteering hose with the C Weight.Its been described in many differant ways but drone and vibration is one of them at speeds you describe.Try truck OUT OF GEAR and rev engine slowly and see if same noises occur.

 

I didn't read that article in MT, but with my 4" Exhaust, it does sound like a dump truck.

GM does put AAM's in there trucks, but not sure if they have the issues your having. You might want to post that question the GM diesel board.

There's been a few threads on 2000 rpm vib's, but I've not been following them since my truck isn't afflicted.

 

Are you kidding? They haven't put a D60 in a truck since the straight axle 1-ton went bye bye in 1992 and the new trucks use an AAM axle.

Andy

 

My vibrations are conciderably less since I drained and refilled with the proper amount of fluid in my 10.5" AAM. I still have a minor driveline angle vibration to take care of but the rumbling vibration I might have to conclude after another couple of highway trips was caused by overfilling the rear end. As odd as it sounds, if an ounce of wheel imbalance will give you the shivers, maybe a quart of fluid being slapped at 700+rpm by the carrier in the rear end can also be felt.

 

I knew this.. I had rock crawling on the brain... the chevy is IFS now..
Scott

 

If only they had Mog axles

Andy