Front End Clunk - Found It!

GMCanuck · December 30, 2010

So I took another look around today for my front end clunk - AND FOUND IT ! ! ! ! !

Turns out that the bushing at the end of the cross-member where the rear of the torsion bar mounts is loose (see photos). The torsion bar is firm in the cross-member, but there is alot of movement and knocking in the connection where the cross-member attaches to the frame. The cross-member moves up and down when I lift the vehicle from belos. And since the rivets holding the bracket to the frame, I am assuming the bushing is worn.

So, anyone know what is involved in replacing these parts? Can this be done with the torsion bar and cross-member in place?

Any thoughts or help would be appreciated.

Thanks in advance.

Beer Belly · December 30, 2010

I had the same problem with mine....the dealer gave a price of $132 done, out the door.....I told him "ok, let's get it done....and by the way, have the tech becareful, I have low speed ABS activation"...after a while, he came out and said "being we are doing one, let's do the other one too"...I said "the funds aren't there, just do the one"....he came out 3 hours later and told me "we did both mounts, and cleaned your ABS sensors...no extra charge"....I just about hit the floor.

thecraft · December 30, 2010

It makes a clunk that feels right underneath your feet, right? I think I have that same problem too then.

az'03Silverado · December 30, 2010

Holy rust Batman! You must live up north somewhere (hence your signature).

GMCanuck · December 31, 2010

It makes a clunk that feels right underneath your feet, right? I think I have that same problem too then.

Exactly - that's why I spent quite bit of effort looking at the front end parts (i.e. ball joints, bearings, bushings, tie-rods, etc.). Finally noticed that when I pushed the front end up and down while standing beside the vehicle, the noise was actually coming from behind the cab. So I lay down on my back, placed my foot under the front fender well, and lifted/dropped the vehicle with my foot while looking around underneath. That's when I noticed the movement in the cross-member - BINGO!!!

Now I just need to fix it...

GMCanuck · December 31, 2010

Holy rust Batman! You must live up north somewhere (hence your signature).

Yes, in the land of snow and ice. Fortunately, our road crews do not use as much salt as some other provinces/states, but still enough to excellerate the rusting process.

Just to be clear, the rust is on the frame rail only. The "rusty-looking" line in the second photo - that looks like the edge of a rusty body panel - is actually just sandy-snow sitting along the top of the nerf bar.

GMCanuck · January 8, 2011

Well, I went out this afternoon to do a little more looking. It seems the torsion bar is actually putting upward pressure on the cross-member. So I'm thinking this should be fairly straight forward - simply place a block between the top of the cross-member and the unerside of the body - this way holding it in position during the work - or simply let it move up and then just pull it back into position following the bracket and bushing replacement.

Now I just need my Helm repair manuals to arrive (on Monday or Tuesday), pick up the parts and get rid of this ANNOYING clunk...

RaddHazzard · January 10, 2011

Keep us updated. Ive got all kinds of clunking under my feet going over the smallest bumps. Ive yet to get under the truck and yank on stuff to see where the play is. If you dont have to remove the torsion bars that would be good news.

GMCanuck · January 10, 2011

Keep us updated. Ive got all kinds of clunking under my feet going over the smallest bumps. Ive yet to get under the truck and yank on stuff to see where the play is. If you dont have to remove the torsion bars that would be good news.

I will certainly post an update once it's fixed. If you are looking at this particular bushing, you may need to use a pry bar to test for movement. The torsion bar seems to keep things pretty stiff in a resting position. Me just pulling on the cross-member did not move anything. I either had to get the truck bouncing, or use a prybar against the frame to get the bushing moving.

Later...

cliobogger · January 10, 2011

"well theres ur problem!" Northern states'll do that to ya. Salt FTL.

Eddie 70 · January 10, 2011

Just out of curiosity, are you changing only the rivets or something else? I was thinking you could knock one rivet out and put a bolt with a nut in it and then replace the other rivet with a bolt and nut.

RaddHazzard · January 10, 2011

I believe he is replacing the bracket as well as the bushing, because it is sold as on piece. The stock part is riveted in, but the one you buy has bolt/nuts so you have to get the rivets out any way of your choosing. My Haynes manual states you can drive the bushing out toward the drivers side after it is "unstaked" but I havent seen just the bushing for sale.

RaddHazzard · January 10, 2011

this

GMCanuck · January 11, 2011

I believe he is replacing the bracket as well as the bushing, because it is sold as on piece. The stock part is riveted in, but the one you buy has bolt/nuts so you have to get the rivets out any way of your choosing...

That's correct. I'll likely be grinding or air chiseling the rivet heads off and then separating the bracket from the frame.

...My Haynes manual states you can drive the bushing out toward the drivers side after it is "unstaked" but I havent seen just the bushing for sale.

Yeah, the dealer told me they are sold together with the bracket. And I suspect by the time I get everything apart, the bracket may not be very "straight"...

As for the bracket/bushing, I assume mine will look slightly different than your photo (since the bushing is perpendicular to the bracket), but it's certainly similar.