OK, here's the deal, a few months back I started noticing a noise from the front end somewhere. It mostly does it when coming to a stop, taking off (even slowly) and sometimes while driving, but doesn't do it when I hit bumps or anything.

Here's what I've done so far, both upper control arm bushings, both upper ball joints, 1 outer tie rod end w/ adjusting sleeve, idler arm, brake calipers, pads and rotors, Rancho RS5000 series shocks, and even 2 new tires.

The lower ball joints and the other 3 tie rod ends all seem to be fine. The only thing that I know has any play at all is the Pittman arm, but its not much at all, you don't notice it driving.

To me, it sounds like it might be in the torsion bars (I don't know what else is left), I've tried adjusting them to several different heights and it hasn't made any difference. Could they or the sway bar make any noise? Its hard to describe, sounds like something shifting, not a pop almost like a rattle but heavy.

I don't know the sound, but normally squeaks are metal to metal contact (as you well know) or when going from rubber to urethane bushings. Did you recently replace the sway bar with urethane bushings? How about the front wheel hub assembly? Not trying to be a PITA, but have you checked your front brakes? I just thought of something too...your A-arm bushings might be wearing out as well. Let me know.


Dan

Wow, I'm an idiot. I didn't read your post very well.

If it sounds like the torsion bars, check to make sure the nut part that holds the adjusting bolt is still in on each side of the crossmember. They can slip forward or back and only be on one edge of the crossmember and will bounce when you hit a bump. Also you might look at the bushing on the transmission, it might be shot or the bolts might be loose. If it was moving it would be in about the same area and make about the same noise.

I don't see any nuts anywhere on the torsion bars, are you talking about the adjusting bolts? They are both there and as I mentioned I've adjusted them to several heights and it hasn't made any difference.

Thats the tranny mount your referring to right _nar_?
Good point, it does mount very close to where the torsion bar adjusters are it it would resonate through the frame similairly.

What is involved in replacing the mount? Should I do motor mounts at the same time? Far as I know they are all original so they're definitely due for replacement.

The part the adjusting bolt goes through, it hangs on each side of the bracket, it can slip forward or back sometimes.

As to the rubber mounts for the trans and motor, pretty sure you can find urethane ones that would be firmer than rubber and better. I know I saw them advertised somewhere. When that rubber gets old it flexs a lot when you get on it. Motor twist you know? If you have someone rev it in park and lay beside it and watch the transmission, see if it really flexes the bushing apart...
When I replaced one on an older truck I just unbolted it, jacked the trans up a little, slipped the old one out and the new one in, then lined the bolts up and started them and then let the trans back down and tightened. Pretty easy.

I wonder if I'm having a simular noise. My truck has a 6" lift that the dealer done. Every once in a while I hear a pop in the front end when I break hard more so on a declined stop. It doesn't do it all the time but it is anoying. It's almost as if when you need to pop your knuckles.

:help:

That sounds very similair to the sound I'm hearing.

Hopefully the source of the noise you hear will be as easy to remedy as mine was.
I just started experiencing this noise while going over small bumps and driving slow or while slowing down.
My hood adjustment screws w/rubber bump stops located at each corner of the hood were loose and backed down so far the hood would bump up and down creating the knocking noises. Only audible while going slow due to less road noise.
I removed the bump stops and placed a 10mm nut on them, adjusted the hood and then locked them in place. No more knockin' & rattlin' noises. :)
Either GM forgot to install locking nuts on mine or that's just the way they built it.

Hmm, I had a buddy with an 04 that was the same way.. We were driving around and it was rattling, driving me nuts.. He said he was gonna take it to the dealer sometime. I couldn't take it, I made him stop and I screwed the stops out a bit so it quit.. Don't know how he could stand it...

Mine just started doing that, thought it was the front end as well. All the bouncing up & down on the front end didn't replicate the sound. The up & down play in the hood was all it was. Thought for sure I'd be able to see the hood shakin' around up there, just wasn't visible, doesn't take much hood movement to cause the knocking noise.
A locknut on the stops is really necessary.

I had the hood off when I changed the heads, and I had a heck of a time realigning everything but I'm confident that's not whats making the noise.

I do appreciate the tips though, I'm going to start with replacing the tranny mount and see how that does.

Have you checked your CV joints? I don't know if yours is 4wd or not, but it's a thought. I know they aren't getting any torque unless in 4wd, but they are still constantly turning and cycling with the suspension.

Z71 Blazer.
Noise doesn't change in 2wd or 4wd.
I found some of the rattling noise to be a couple of loose bolts holding the bumper on, but it was definitely a different noise.

Had a noise in my front-end that sounded for all the world like it was in the rear-end.....It was the passenger lower shock bolt was loose!! Check the torque on the shock bolts if you've changed from stock.

Hope this helps someone............:D

Had a noise in my front-end that sounded for all the world like it was in the rear-end.....It was the passenger lower shock bolt was loose!! Check the torque on the shock bolts if you've changed from stock.

Hope this helps someone............:D


I have after market shocks, I'll look into it. Thanks...

:cool2:

Have you found out the cause yet? I've had my 04 in FOUR times to GM in the past two months for the same "popping/clunking" noise. Passenger side to centre front end. Almost every left turn while decelerating through the turn.

PLEASE - can anyone help me? GM has commited to finding the problem, but hiding or disconnecting my juice attitude and box every time is becoming a huge PITA. Had stock shocks on when noise started couple months ago (after a year of perfect quiet). Switched to Bilsteins, same noise, getting worse actually. GM has looked at all front end components four times (b-joints, t bars, pitme, t-rods etc) and swears (in writing on my service record) no problems. I have no steering vibration or pull.

Been under the truck 20 times, no signs of metal on metal contact anywhere. GM lubed the steering shaft or whatever it is too. Still making then noise on 90% of all turns.

IT"S DRIVIN' ME NUTZ!!!!!!!!!!

Have you found out the cause yet? I've had my 04 in FOUR times to GM in the past two months for the same "popping/clunking" noise. Passenger side to centre front end. Almost every left turn while decelerating through the turn.

PLEASE - can anyone help me? GM has commited to finding the problem, but hiding or disconnecting my juice attitude and box every time is becoming a huge PITA. Had stock shocks on when noise started couple months ago (after a year of perfect quiet). Switched to Bilsteins, same noise, getting worse actually. GM has looked at all front end components four times (b-joints, t bars, pitme, t-rods etc) and swears (in writing on my service record) no problems. I have no steering vibration or pull.

Been under the truck 20 times, no signs of metal on metal contact anywhere. GM lubed the steering shaft or whatever it is too. Still making then noise on 90% of all turns.

IT"S DRIVIN' ME NUTZ!!!!!!!!!!

I'd still check those CV joints out.

I'll take your advice and look at them more closely. I noticed some minor oil sweating out of the one on the passenger side a while ago - wonder if that's a clue???

Thanks.

Did the popping noise seem to come from the drivers door area or the front end? Mine seems to come from the door but cannot hear it when the window is down

Had a noise in the right front when hitting bump,loader when braking.Found the passenger side front nerf bar mount hitting the frame,loosened it and pulled it back.Noise gone...

I had a "popping/snapping" noise that sounded like it was in the front-end somewhere on my 2004 2500HD. It was most noticeable when backing and turning, while using the brakes. Especially on an uneven surface.

A Dealer Service Tech diagnosed it right away, when he heard my description.
Turns out the problem was metal to metal contact where the cross-member, under the engine/transmission, is mounted. I greased all the contact points of the nuts, bolts, cross-member and frame bolt sleeves. Noise gone! Apparently the torque on the frame and friction of the moving parts was causing the problem. Dealer would have fixed it, under warranty, but it was faster to do it myself. A 30 minute job.