Rattling Sound From Rear and Highway Vibration

[KerryBoehm]

This is on a 2007 GMC Yukon XLT 1500 4WD with about 130K miles. Noticed this last weekend while on a longish highway trip last weekend. At 75 mph there is an annoying vibration seemingly coming from the rear of the vehicle. At 80 it mostly goes away.

This weekend I rotated the tires to see if the vibration moves to the front and afterwards drove around on side streets a bit with the windows down. Got some looks being temps are in the 20's here. Anyway, I notice often when accelerating from a dead stop I hear a loud tapping sound up to about 20mph.

I'm suspecting differential, U joints, or transfer case. Anyone have any suggestions?

 

[petethepug]

If it’s at the rear, you’re right, u joints, diff or loose lugs on a rim. Rear of these vehicles usually pretty uneventful.

 

[KerryBoehm]

I can rule out loose lugs. I rotated tires and they were all tight. My Kobalt impact struggled a bit getting them off in the below freezing temps. Taking it out today I'm sure the vibration will still be there. Next I'll jack up the rear wheels and see if I can replicate the noise I'm hearing spinning them by hand

 

[Joseph Garcia]

Welcome to the Forum from NH.

Lots of knowledgeable folks here who freely share their knowledge, experiences, and perspectives. Knowledge is power.

I hope that you will become a participating member in the Forum's discussions.

Pics of the truck, please.

You are already receiving clarifying questions from the knowledgeable folks on this Forum.

 

[rdezs]

I wouldn't rule out the transfer case, either. Look for any sign of leakage at either output shaft seals. More likely it would be the rear seal, indicating the bearing that supports the output shaft has worn out. Grab your drive shaft where it goes into the transfer case and try to move up and down. If it moves you've confirmed it. That would likely send a vibration down the length of the drive shaft, and the drive shaft itself would have issues being out of balance in effect. Tapping sound could be the drive chain in the transfer case. If the bearings are that worn, you'll get more slack in the chain and it will tap against the case. And as you know, sound travels and it's hard to determine exactly where it's coming from sitting behind the wheel.

.... Or a really bad u-joint but I think you would have seen that?

 

[ScottyBoy]

I had similar symptoms on my 2001. But I also had some clunking noises when driving low speed over bumps, like speed bumps in a parking lot. It turned out to be the pinion bearings in my rear differential. I'm NOT saying that's what is wrong with yours, but I wouldn't rule it out, it's definitely worth checking it to rule it out.

 

[rdezs]

He really needs to get under there and check the whole drivetrain. All the way to the caliper mounts, and check for axle end and radial play.

Vibration quits at 80 mph.... Lol, that takes some nerve going that fast knowing there's something wrong!

 

[Doubeleive]

This is on a 2007 GMC Yukon XLT 1500 4WD with about 130K miles. Noticed this last weekend while on a longish highway trip last weekend. At 75 mph there is an annoying vibration seemingly coming from the rear of the vehicle. At 80 it mostly goes away.

This weekend I rotated the tires to see if the vibration moves to the front and afterwards drove around on side streets a bit with the windows down. Got some looks being temps are in the 20's here. Anyway, I notice often when accelerating from a dead stop I hear a loud tapping sound up to about 20mph.

I'm suspecting differential, U joints, or transfer case. Anyone have any suggestions?

sounds like drive shaft/u-joints to me
rotational noise is different than just rattles
your definition of the noise sounds rotational
but if you haven't changed the rear differential gear oil out yet, now would be a good time to take a look in there for metal
if the rear diff or ring/pinion is leaking that would be a sign, or the oil has leaked out.