I have a 2006 Hummer H2, I recently took it on a road trip up t the Badlands. While I was there, I noticed a popping noise while climbing some steep dirt roads. It continued on the ride home only during a few instances:

1. If I gun it a bit after coming to a complete stop.
2. If the vehicle was in Cruise Control and we went up a steep hill, if the engine needed to get to 4k rpm I would hear it pop.

These are the only times it would pop, at the first instance, it only pops if the vehicle is traveling about 5-25 mph. after this no noise until you hit 4k rpm. I am thinking it could be my differential slipping, not 100%. Any ideas? The Transmission was serviced, flushed and refilled and the noise is still present.

TIA

 

It should be noted this is a CLUNKING noise, not a popping noise. I was corrected by someone who heard it.

 

Welcome to HF. Please help us all out, READ before you post anything as you posted this in the New Member Section which at the top in a sticky threads says: "THIS SECTION IS NOT FOR TECH QUESTIONS!!." That section is only for introducing yourself and letting us know what Hummer you have or are interested in.... anyways.

All questions regarding H2s go in the H2 section where I moved this for you, so members that have H2s can assist you.

Differentials do not slip. You could have many possible causes for your popping/clunking, like a stretched T Case chain jumping a tooth, bad U Joint, etc... I am sure some H2 peeps will stop by and lend their thoughts to help.

Good luck.

 

Thanks for moving to the correct thread, I was able to get under the vehicle and take some pics of the U Joints, see below. They look fine to me, thoughts? I did notice the rear stabilizer bar bushing on my driver side was split, could this be the culprit?

 

I have an 08 and was getting a big clunk from take off. Your problem sounds a little different but could be the same problem I had. Check the bolts that hold your front diff in place. On my 08 there are 3 bolts that had come loose, and everytime I would take off the front diff was flexing cause it wasn't bolted down tight anymore. I replaced the bolts and the clunk stopped

 

The bolt that was the main problem was located right next to the oil filter. I moved the bolt and it hit the frame or whatever it bolts to and got the same clunk I was hearing everytiime I pulled off. As bad as it sounded I couldn't belive it was that simple

 

Thanks for the advice, I think I found the issue,

 

Transfer case needs rebuild possibly to include rear case half.

 

Changed both U Joints on my rear shaft, now the knocking has moved from the rear driver side to right under the driver seat. I am guessing the U joints on the front shaft are bad as well. Tried to pull the shaft out of the transfer case... it would not come.. .am I missing something?

 

Yes, a certified technician!