Archived Rolling thump

[BHumphrey]

While rolling backwards, after gently depressing the brake my truck makes a pretty loud bump. It sounds just like I am hitting a curb or grocery cart. I visually checked all external bolts and shackles and they seem fine. Has anyone else experienced this?





2000' 2500 QC LB 4X4 6spd

 

[JayWm]

Is it coming from the front or back? First thought would be to check lower control arms and the front shocks. I'd suggest putting an air gun to the top shock mounts. They are hard to get tight and prone to knocking if not tight.

 

[BHumphrey]

feels like it's coming from the back

 

[Woodenhead]

Does a '00 have discs or drums in the back? If it has drums, I'd pull em to see if something happened with the brake setup. Maybe a separated shoe. Any chance you've got a severly toasted U joint.

 

[BHumphrey]

i'll check both of those, I am pretty sure it is brake related though, it only occurs when brakes are actuated.

 

[BHumphrey]

Checked front and rear brakes and ujoints and visually checked shackles. It occurs when rolling backwards and applying the brakes after having had applied the brakes when moving forward.

 

[Woodenhead]

I know you said you checked the brakes but it sounds like a caliper (if rear disks), pad or mounting bracket that could maybe be loose. Try putting the rear end up on stands and see if you can repeat the noise. If so, you may be able to have someone do it while you're looking.

 

[RAJohnson]

Make sure all things are secure in the cab of the truck and also in the bed.



I once had a alignment done and took it for a drive and had a clunk. Sure sounded like it was in the front end. Could not find it Took the mechanic for a ride who did the front end, he heard it and put it back on the rack, and found nothing :{ Took it for another drive and it was still there. We went back to the rack and just before pulling on I looked under the front seat and my towing mirror was rocking back and forth when ever you gave it the wood or braked real hard.



Just a thought.

 

[DBraunig]

If you got a buddy you trust enough , have him hold his hand on the front upper ball joint/knuckle area and to see if he can feel it, then try the rear as well, top of spring pack. You should be able isolate to the front or rear that way. We had a couple trucks through the years with a similiar complaint and it was the front lower ball joints... they were loose enough to shift when braking, you could actually see them move once we figured out what was going on.



Dave