Thump clunk rear end

[5strmtrp]

Hey all,

My Tahoe has developed a thunk clunk when you give it the go juice from a stop.

It’s definitely feeling like it is in the rear or the truck.

Checked the control arms, shocks, and driveshaft, not seeing anything out of the ordinary.

It has had a rattle sound from the back since I got it nearly 3 years ago but never had any of the above symptoms.

It also seems like it affecting acceleration and keeping the momentum going on the road.

As always appreciate the feedback and help.

 

[robgreg75]

I thought at first my rear end was clunking but then realized it was the motor mount gone and the clunk was just the engine moving.

 

[5strmtrp]

Hmmmm I’ll check into that, worth the few minutes to check. To me it seems as if it’s in the rear of the truck, but can see how the feel and noise transfer backwards from a stop.

 

[jeremiahm]

Mine does the same thing, thought it was in the rear but after replacing everything (it was needed), that thunk was still there. After a bunch of reading I determined it is the driver motor mount. You will find lots of write-ups on here. When you do it you will want to do the hummer solid rubber mounts as listed in the sticky on this forum. One way to test the driver mount is by revving the engine in park and watching it move up and down on that side. Mine comes up 1/2" or so. Also, my mount is so bad the fluid is leaking out and leaves drips, at least that's where the leak is coming from, motor is nice and dry.

 

[jeremiahm]

Motor Mount sticky: https://www.tahoeyukonforum.com/threads/broken-motor-mounts.55790/

 

[OR VietVet]

You will want to set parking brake and then have a trusted friend hold the brake pedal hard and "goose" the engine in drive and in reverse to check the mounts movement. I would also want to be under the rig and check the transmission mount. This last part is where you really need to trust the friend doing the accel for mounts movement. You can also block all wheels too during this process.

 

[swathdiver]

My Tahoe has developed a thunk clunk when you give it the go juice from a stop.

It’s definitely feeling like it is in the rear or the truck.

Very likely time for a new driver's side motor mount. Been there, felt that, done that!

 

[donjetman]

My Klunk was caused mainly by the wore out front differential bushings. I changed my motor and tranny mounts while I was at it: https://www.tahoeyukonforum.com/threads/no-more-klunk-yeah.134250/

 

[Geotrash]

My Klunk was caused mainly by the wore out front differential bushings. I changed my motor and tranny mounts while I was at it: https://www.tahoeyukonforum.com/threads/no-more-klunk-yeah.134250/

+1. That was my situation in my ‘07 as well.

 

[Joseph Garcia]

+2 on the differential mounts for my 07.

 

[89Suburban]

Could also be worn spider gears in the rear axle.

 

[donjetman]

The chain etc is loose/worn in my 177k mile awd tranfer case. Its on my list of things to do.

 

[5strmtrp]

Thanks all will take a look at engine and differential mounts this weekend. I’ll post my findings.