Canadian Hummer Club Forums

So i have had a thumping noise in the truck since i bought it. Was told when it got safetied it needed a few ujoints and a hanger bearing. I have done them all. The thumping is not there when i first start driving but starts from what i can tell after something warms up. The thumping is when i am on the gas and not there when off the gas but is also there when i am on the brakes. The thumping is a rotoation thump. If that makes sence. I have checked all the wheel bearings/hubs. No play. The halfshafts are not loose in the hubs. All brake parts/bolts are tight. Hubs have clean and full of oil. Rear calipers have a bit of wiggle and a squeak when moved by hand. When i rotate each tire when raised all feels good. I am baffled! If i let the truck sit for an hour or so it is gone but comes back again once " i think", something heats up again" like the brakes maybe". Oh and the two inner cv boots are ripped so possible bad cv but they have no play in them.


I am at the point my next step is to replace the boots clean and regrease the halfshafts and replace all the brakes on the rear and hope it is one of them.


Any ideas?


I know diagnosing a noise without hearing it tuff! Lol


Also what brakes do.you guys run. I ordered napa stuff but not sure i want them.

It sounds like you have already checked a lot of possible sources. My issue I believe is coming from my passenger side wheel hub. Funny thing is, if you spin the wheel, smooth silent rotation, if you spin the shaft input gross mechanical gear noises.


It might be worth checking your hubs.


A good point Roy had was to try and get an idea of the frequency of the noise, as in; the halfshaft (and brake rotors) spin twice as fast as the wheel, and the the driveshaft three times (roughly) as fast as the halfshaft.... that may give you an idea of where to focus.


Check my thread for other ideas from the good fellas on this site...


Wolf

For brakes don't get "cheap" its worth the start to get either severe heavy duty or AM pGeneral pad,

Lol my first time I went cheap, and the pads were gone in under a year, now at year 5 and still good...with the pads i got off Roy shop.

Those were factory pads I believe...

Ya, thumping one would have to listen to, not sure if metallic thump or say tire thump ...

Ball joints (if worn can)

Weird on how it starts when warm,.. Maybe your right on the half shaft, plussss, once it's greased and checked over your good for a while and lol, confident on them when on the road...

Even can be rotors , so hard to think of it

My ctis wheel shield always made a noise that drove me nuts, now with the wheel protectors on, super quiet, heheh

Did you happen to check the large caliper carrier bolts? Sometimes those can start to back out and contact the output flanges.

You have already checked everything that would be the normal source of the issues.

Do you have 2piece wheels with the one piece runflat or the 2piece runflat with 1 piece wheels? Sometimes the 2 piece runflats make a weird thump like this.

Any way you could record a video?

Actually if your are close to Roy's Shop he could throw it on his lift and probably find the issue in under 1 min!

Thanks guys. I will figure it out eventually. I have been fallowing your post Wolf. Thats why i checked soo much! Lol.

Possibilites:
 
1) Behind the rotors, there are 2 bolts that hold the caliper mounts on, these loosen up and contact the cv shaft retaining bolt ends
2) the cv bolts loosen and contact the alum brake bracket.
3) brake pads are slapping against the retaining brackets--worn out brackets
4) cv shaft ends have dirt in them
5) crankshaft balancer worn out--belt runs on this
6) driveshaft not aligned at slip joint--out of rotation when hanger brg fixed
....
 
every one will give you a noise
Drop by and we can figure this out quickly. You are only an hour plus away. Tag Monk and drive down together.
No worries if you brake on the way, I have a trailer to pick up up.

Thanks Roy!
 
I will check these that I have not already done. I would love to come up. I will need a couple of weeks and yes maybe Monk would like to come up as well.
 
I now see your site/number on your post!!!  LOL

Thing I like about Roy's place, is he'll show ya the issues, and teach you for possible future repair, (that's if you enjoy to work on your own rig, like me,) this really helps with stuff

Sounds like a road trip to me!
 
 
Short one, LOL