Slight "thud" on moderate accel from standstill

Disclaimer: Links on this page pointing to Amazon, eBay and other sites may include affiliate code. If you click them and make a purchase, we may earn a small commission.

OP
OP
B

Bucky1

Full Access Member
Joined
Jun 15, 2018
Posts
110
Reaction score
41
I noticed today that it will not do it power braking. Only after it starts to move does it pop. Almost sounds like something in the front right shock. I believe that is an air ride control if I remember correctly.
 

wjburken

Supporting Member
Joined
Dec 26, 2017
Posts
9,923
Reaction score
27,405
Location
Eastern Iowa
I have had various causes for clunks when taking off from a stand still, most of which have been mentioned here.

With 130K, it could very well be a front shock. That’s close to when my front shocks have out on my ‘07 XL Denali. I would also inspect your drive axle as the boots like to split and let all the grease out.
 
OP
OP
B

Bucky1

Full Access Member
Joined
Jun 15, 2018
Posts
110
Reaction score
41
OK. Great stuff. I checked the ball joints with my regular method and they appeared to be tight. But it is something I have missed.
 

kbuskill

***CAUTION*** I do my own stunts!
Joined
Mar 11, 2017
Posts
5,299
Reaction score
8,299
Location
NE. FL.
There is no "air ride" up front, only on the rear if you have the "auto leveling" rear suspension RPO code Z69.

However all 4 shocks/struts are electronically dampened if you have the "autoride" suspension RPO code Z55.

There is also "Magnaride" suspension but the RPO code escapes my memory at the moment. But James @swathdiver knows.

If it sounds like it is coming from the front it could be a bad spring isolator allowing the spring to pop and make noise... a bad upper or lower control arm bushing... a bad sway bar end link or bushing.
 

avalonandl

Full Access Member
Joined
Apr 6, 2019
Posts
2,200
Reaction score
2,635
Location
Troy, MICH & Naples, FL
My AWD 2011 Denali (134k miles) does the exact same thing- not all the time.

Its not the motor mount because I did the throttle blip with hood up- ZERO movement.
 

09_4WD_YUKON

Full Access Member
Joined
Mar 23, 2018
Posts
194
Reaction score
124
I think I have the same thing as you, but have not checked mine out. I also think someone on here mentioned checking the rear trailing arm bushings.
 

CrashTestDummy

Full Access Member
Joined
Feb 18, 2014
Posts
883
Reaction score
324
Location
Pearland, Texas
At >100K miles, if you haven't replaced a motor mount, it is the motor mount. AND in the outside chance it is not, it soon will be, so replacing the driver's side motor mount with the Hummer mount will be money well spent.
 

Rob Haag

TYF Newbie
Joined
Aug 10, 2016
Posts
4
Reaction score
1
Location
Columbus, OH
Mine turned out to be rear control arm bushings, I had a rattle with it too, over the slightest bumps, that drove me crazy. I had to move my axle just a bit when I installed the new trackbar, all the bushings back there were worn. Thux and rattle is gone now, I originally thought it was u-joints or transfer case
 

Forum statistics

Threads
132,089
Posts
1,862,177
Members
96,557
Latest member
Harald1959
Top