Noise in rear of suburban

[Tom Charles]

I just started pulling a pop up and have quickly developed a noise coming from the back axle. Sounds is like when a  loose muffler wiggles.
It is not the muffler.  Any ideas?  I have pulled only 60 miles, but while practicing parking, I could have put too much stress on the truck by
jack knifing the trailer. Help

[PattieAM]

I just started pulling a pop up and have quickly developed a noise coming from the back axle. Sounds is like when a  loose muffler wiggles.
It is not the muffler.  Any ideas?  I have pulled only 60 miles, but while practicing parking, I could have put too much stress on the truck by
jack knifing the trailer. Help

Does this noise occur only when towing or now all the time?

It could be 'anything' - shocks, springs, rear differential.  If you can get under the vehicle, trace back from the hitch and see what's connected to what, and maybe you can see what might have been loosened by the weight of towing the camper.

[Tom Charles]

Does this noise occur only when towing or now all the time?

It could be 'anything' - shocks, springs, rear differential.  If you can get under the vehicle, trace back from the hitch and see what's connected to what, and maybe you can see what might have been loosened by the weight of towing the camper.

Occurs when I start to drive for about 3 seconds, maybe at 10 mph then goes away. I do not have the camper attached .  Does not happen when I ramp up the rpm while in park.

[austinado16]

Suburbans are too tough to hurt towing something as small and light as a camper.

If you can provide more info, that would help us help you: year, model, and mileage, what does the noise sound like, does it do it with the camper in tow, etc.

[Tom Charles]

Does this noise occur only when towing or now all the time?

It could be 'anything' - shocks, springs, rear differential.  If you can get under the vehicle, trace back from the hitch and see what's connected to what, and maybe you can see what might have been loosened by the weight of towing the camper.

Occurs when I start to drive for about 3 seconds, maybe at 10 mph then goes away. I do not have the camper attached .  Does not happen when I ramp up the rpm while in park.

[Tom Charles]

Suburbans are too tough to hurt towing something as small and light as a camper.

If you can provide more info, that would help us help you: year, model, and mileage, what does the noise sound like, does it do it with the camper in tow, etc.

I have a 2006 suburban LT with 48000 miles new tires. Strong truck, and you are correct, I didn't expect any towing trouble.  But after my first tow, I have this bad noise.  Sounds like a loose muffler or loose license plate ( that is as close as I can describe)
( both do not rattle) .  I am thinking transmission or differential.
I have not tried the towing with camper again.  Question is do I go to the dealer or to AAmco or where?

[austinado16]

At 48,000mi is it still under warranty for drivetrain, etc.?  The exhaust system certainly is.

Avoid places like AAMCO, Midas, Meineke, Jiffy Lube, and all other schlock chains like the plague......unless you want to spend a ton of money and have your nice 'burb (or anything else you own) really screwed up.

So the noise occurs only when the truck is moving, and only under that initial application of power?  Try stepping down hard on the brakes and then apply some throttle like you are trying to take off.  See if it does it then.

I'd also throw down a blanket, crawl under, and bang on the muffler, and the catalytic convertor with the side of my fist (like a hammer) and see if they rattle inside.  Do the same to the rear license plate and it's frame.  If you don't find anything, I'd go visit the dealer.

Sometimes with these trucks that have 2 big frame members under the body, a noise in one location can resonate and sound like it's coming from somewhere else.  Case in point; I just had a failed left rear wheel bearing (250,000mi) and it had started to eat into the left axle.  The noise sounded like it was coming from the driver's side front wheel bearings....so much so, that I repacked both front bearing sets.  That didn't cure it, so I replaced the bearings, which still didn't cure it.  It was then that I knew.....hey, it must not be coming from the front end!!

[wernstriumph]

Sounds to me like you may have a bad U-Joint on the drive shaft back by the pinion gear. check to see if there's any slop in the shaft. Also does it have a two piece driveshaft? I had an old Bronco that had a two piece and the spot where they slide together was sloppy. it used to make a rattling sound when I first moved from a stop.
Hope this helped, Good luck!

[Tom Charles]

At 48,000mi is it still under warranty for drivetrain, etc.?  The exhaust system certainly is.

Avoid places like AAMCO, Midas, Meineke, Jiffy Lube, and all other schlock chains like the plague......unless you want to spend a ton of money and have your nice 'burb (or anything else you own) really screwed up.

So the noise occurs only when the truck is moving, and only under that initial application of power?  Try stepping down hard on the brakes and then apply some throttle like you are trying to take off.  See if it does it then.

I'd also throw down a blanket, crawl under, and bang on the muffler, and the catalytic convertor with the side of my fist (like a hammer) and see if they rattle inside.  Do the same to the rear license plate and it's frame.  If you don't find anything, I'd go visit the dealer.

Sometimes with these trucks that have 2 big frame members under the body, a noise in one location can resonate and sound like it's coming from somewhere else.  Case in point; I just had a failed left rear wheel bearing (250,000mi) and it had started to eat into the left axle.  The noise sounded like it was coming from the driver's side front wheel bearings....so much so, that I repacked both front bearing sets.  That didn't cure it, so I replaced the bearings, which still didn't cure it.  It was then that I knew.....hey, it must not be coming from the front end!!

As a follow up, thanks for your help.  I took the truck to the local chevy dealer and they come up with loose baffles inside the muffler.  
Replaced the muffler and no noise.  mUst have been a coincedence that it went bad on the initial pull of the camper. Oh well. I am fixed and ready for my journey.  Thanks again for your time and imput  Tom

[PattieAM]

Thanks for following up on your initial post - much appreciated by all readers.

['tiredTeacher]

I have a 2006 suburban LT with 48000 miles new tires. Strong truck, and you are correct, I didn't expect any towing trouble.  But after my first tow, I have this bad noise.

Are you leaving the drawbar in the receiver? That will rattle, you betcha.

[austinado16]

As a follow up, thanks for your help.  I took the truck to the local chevy dealer and they come up with loose baffles inside the muffler.  
Replaced the muffler and no noise.  mUst have been a coincedence that it went bad on the initial pull of the camper. Oh well. I am fixed and ready for my journey.  Thanks again for your time and imput  Tom

Ah yes, the ol' bad muffler baffles.  Thought so.  Hopefully you got a new one under warranty because that's super early for a failed muffler in one of these trucks.  I think I finally replaced my truck's original one at 230,000mi.

Glad you got it fixed and that it was something simple and easy.  I'm also glad you fixed it with OE GM parts.