Sounds like a rattling noise coming from the front passenger side

SWEETIE1965

MEMBER
2004 GMC ENVOY
4.2L
6 CYL
4WD
AUTOMATIC
189,000 MILES

I have checked all ball joints. I've changed both upper control arms due to worn bushings. I've changed both upper ball joints. I've checked entire suspension system in front and rear. I keep hearing a rattling noise coming from the front passenger side or so it sounds like that. No noises when I pass over bumps on roads though. I checked the sway bar bushing and links. Everything seems fine. Now for the last couple days the noise is starting in the rear too. I just can't figure out where the noise is coming from. I have a front CV shift to replace. That is one thing I can hear at low speed. But everything else is a mystery. I've inspected the entire front suspension but can not pin point where the noise is coming from.

Thursday, August 12th, 2021 AT 5:52 PM

1 Reply

CARADIODOC

MECHANIC
34,330 POSTS

I have two thing to get you started. The first is covered in this service bulletin. It involves rattles caused by the hood. If you can't read it, you can copy and paste it into an MS Word typing program, or I can reformat it into pieces that I can expand for you.

Second, an elusive thumping type of rattle was often caused by broken cross member mounts on older models. I can't find a drawing to show if this applies to models as new as yours, but it's worth looking at. On vehicles with torsion bar front suspension, the rears of the two bars are anchored in sockets welded to the cross member behind the transmission. Rather than bolting that cross member directly to the frame rails, it was mounted on a pair of rubber isolators, one on each side. The rubber would tear apart, allowing the cross member to bounce up and down. You can see that real easily by prying up on the cross member with a pry bar. You don't have to wind the torsion bars down to lower the load on the bars to replace those mounts. Just remove the two nuts on the bottom of the frame rail, lift that end of the cross member up with the pry bay, and wiggle the old mount out.

Let me know what you find with these two things.

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