Thump in floorboard can’t fine source

[Doubeleive]

could be the main support-crossmember under the motor/trans, there was a tsb on the NBS for the same issue, the fix was to replace or swap the bolts around and be sure it was all very tight! mine used to do that and it would drive me crazy, same with the rear torsion bar right behind the rear diff, if that was not tight it would "pop" then it just got so worn out I had to replace it.

 

[Doubeleive]

I also had a issue once with the drivers side lower control arm bolt was loose and had worn a egg shaped hole in the frame, had looked at it 50 times and didn't see it, I ended up welding a big thick washer to the frame which worked out just right because the bolt is plenty long enough

 

[guy from norcal]

I'm going with body mounts also. Rock auto has the best price for them.

 

[gpd4]

Motor mounts?

 

[Warriorpluto]

I'm going with body mounts also. Rock auto has the best price for them.

Hop do you change body mounts

 

[kbuskill]

Hop do you change body mounts

Preferably with a lift, but it can be done with jacks and blocks. The trick is you have to loosen/unbolt ALL the mounts or you won't be able to lift the body high enough off the frame to R&R the mounts.

 

[Ponchonutty]

Well I think my sound is actually coming from the rear trailing arms. I’m going to replace all of them once the parts arrive. One lower came in and I replaced the passenger side with it. It already feels better and haven’t heard the actual pop noise since I replaced it

 

[NGAneer]

I'm getting a similar noise when turning right at low speeds, feels like it's under the driver floor. Ball joints, struts and all sway bar hardware is new. I'll have to roll my windows down next time I find one of those familiar places and see if I can tell front or rear. I'd thought tie rods until now.

 

[Ponchonutty]

Well replaced all rear trailing arms. Uppers and lowers are new. Feels tighter in the rear but noise is still there. I think I may try bodymounts next

 

[rscalfani]

@Doubeleive do you happen to have that TSB for the crossmember?

could be the main support-crossmember under the motor/trans, there was a tsb on the NBS for the same issue, the fix was to replace or swap the bolts around and be sure it was all very tight! mine used to do that and it would drive me crazy, same with the rear torsion bar right behind the rear diff, if that was not tight it would "pop" then it just got so worn out I had to replace it.