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96 GMC Jimmy thump under feet when turning


car_guy_88
10-10-2006, 07:55 PM
hey, i have a 1996 GMC Jimmy...just got it a few weeks ago, and im impressed..but one question, just within the past week or so, every time i turn a corner or have to stop very suddenly, i feel a thump under my feet...is this a tie rod issue?? hopefully something i can fix myself..any help would be appreciated..thanx

DelCoch
10-11-2006, 03:18 AM
Is this a 4x4?

car_guy_88
10-11-2006, 02:54 PM
Yes, this is a 4X4 Jimmy SLE...and it just so you know, it makes the noise when i turn left and right

herkyhawki
10-11-2006, 03:00 PM
check your stabilizer bar bushings. bushing kits are cheap at auto part store.

car_guy_88
10-11-2006, 03:05 PM
ok sounds great, yea i didnt even think of that..but thanks for the advice, ill check those out as soon as i can....and just outta curiousity..how much are we talking for the bushings? cuz im a lil low on cash right now..so im just wondering how much they are

DelCoch
10-12-2006, 09:08 AM
They're like 10 bucks or less, for a set of 2 - take an old one with you to the parts store to make sure you get the right ones, as they come in different sizes.

jdmccright
10-18-2006, 04:49 PM
I have a follow-up question related to this thread. I recently replaced all the front bushings and stabilizer bar mounts with polyurethane and now I get the same thumping sound when I am turning and go over an uneven surface (i.e. one front wheel goes up or down relative to the other).

I know that I torqued everything to spec with the exception of the sway bar to a-arm bolt which said 132 in-lb (or 11 ft-lb). Since the nuts used are the nylon insert type lock nut, that can affect the torque applied, so to me it felt that they weren't tightened enough, but have no way of knowing for sure. Of course, no instructions for the sway bar bushings were included in the package. Any suggestions on how to correctly torque these bolts?

jdmccright
10-24-2006, 10:00 AM
Here's a follow-up to my own question. It turns out that the thumping I was hearing was caused by the end of the sway-bar link bolt getting caught up with the tie rod adjustment tube bolts. It was sticking up and was long enough (abt 1/2" above the nut top) plus the tube was positioned just right so that as I turned and the suspension flexed, they would interfere with each other, causing the thump sound as they got caught up and then released. I solved it (at least temporarily) by reinserting the sway-bar to control arm bolt with the threaded end pointing down. Not perfect for those needing ground clearance, but I'm not one of them. Still haven't found the right torque method...just tightened them down to reasonably firm with a box-end wrench.

trackrat
10-30-2006, 08:55 PM
I had the same problem. Make sure That your upper and lower ball joint bolts are tightened properly. I took it to 3 stealers(dealers) and they couldn't figure it out untill I took it to the dealership where I purchased the truck. They tightened them up at no charge and took care of my thumping problem.

It seems that the least looked at solution is never looked at at all.....

Hope this helps.

BlazerLT
10-30-2006, 10:15 PM
http://www.automotiveforums.com/vbulletin/showthread.php?t=302656

Had the clunk as well, it is the hood.

Install these washers and it will go away.

DO NOT DO ANY FRONT END WORK UNTIL YOU DO THIS OR YOU WILL BE WASTING MONEY.

jdmccright
11-01-2006, 10:52 AM
Well, the stuff I did replace did need to be and the interference was an issue as well. And I did use a torque wrench for all of the suspension bolts, though truthfully, the ball joint to arm bolt spec (~17 lb-ft?) was at the low end of my wrench's range (10-150 lb-ft). Hafta crawl back under & recheck....thanks for the tip.

But I do want to do this hood fix too...can you only get the washers from the dealer? Do you have a part number or service bulletin number to refer to (the link you gave was dead)? Thanks!

BlazerLT
11-01-2006, 01:50 PM
Well, the stuff I did replace did need to be and the interference was an issue as well. And I did use a torque wrench for all of the suspension bolts, though truthfully, the ball joint to arm bolt spec (~17 lb-ft?) was at the low end of my wrench's range (10-150 lb-ft). Hafta crawl back under & recheck....thanks for the tip.

But I do want to do this hood fix too...can you only get the washers from the dealer? Do you have a part number or service bulletin number to refer to (the link you gave was dead)? Thanks!

All the information is in that thread.

jdmccright
11-13-2006, 11:07 AM
Well, I did the hood hinge fix but that wasn't it. i'm hearing two distinct types of clunks. One is when the suspension deflects from side to side (going over a dip at an angle) and the other is when I accelerate from a stop.
I've checked my torque wrench and found that it is low by 12-15 lb-ft from the dialed in number. That can mean all the suspension bolts are not tight enough. What a PITA....
The acceleration clunk I hear can be a bad u-joint somewhere or maybe a bad front CV joint (seems to be coming from the front left side) though I hear it even though I'm in 2wd mode...that or the front driveshaft u-joints. Will keep this updated!

BlazerLT
11-13-2006, 12:39 PM
1.) Swap bar end links and bushings. If you hear the clunk in the front when the truck sways, that is usually the problem.

2.) Acceleration clunk is the u-joint or the rear springs and spring bushings need to be sprayed down with oil so they don't catch.

jdmccright
11-13-2006, 01:49 PM
Swap bar end links which way? Left to right? Flip them (head end on top versus head end on bottom)? As stated before, I flipped them head end up to prevent interference with the tie rods. They're both the same, so how will swapping them left/right improve it? Please clarify.

Also gonna look into getting a calibrated torque wrench and retorque all the suspension parts. I appreciate all the suggestions.

BlazerLT
11-13-2006, 02:14 PM
They are new I take it?

Did you replace the sway bar bushings as well?

jdmccright
11-13-2006, 04:01 PM
The sounds did not start until after I replaced all of the following:

Upper and lower control arm bushings (polyurethane)
Sway bar frame mounts and end links (polyurethane)
Upper and lower ball joints (both sides)
Idler arm

The only other thing that remains suspicious that I have been noticing since then is that the lower ball joint grease boots never seem to appear filled despite repeated pumps. Could perhaps be defective or prematurely worn ball joints. Thanks for the help!

BlazerLT
11-14-2006, 02:32 AM
Remember, only grease your balljoints with the weight off of the wheel.

Jack the side up and grease them drop and repeat for the other side.

With the weight on the wheel, grease can't force its way in.

car_guy_88
11-14-2006, 02:15 PM
well heres the thing, i've been so busy i havent had a chance to roll under the truck and look and check out the stablizer bushings, BUT since i posted last, i've realized something, the thumping im feeling under my feet is NOT when im turning left and right, but instead when im hitting the brake. Any ideas? im not sure if that is still a bushing matter or what.

jdmccright
11-22-2006, 10:43 AM
An update on my situation: I have tested my torque wrench and found it out of calibration by about 12-14 ft-lbs on the low side, which is significant at the low end. After retightening the ball joint, control arm, and sway bar bolts, the clunk noise is better but is still significant on the right side when that wheel flexes upwards first over an off-angle dip. The intermittent clunk sound on the left (under my feet) upon acceleration is unaffected. The hunt continues....

laxman21
11-22-2006, 11:13 AM
Check your torsion bar insulators. When they go bad(tear) they allow the rear of the bar to bounce up and down when you go over bumps and make a thumping noise.

jdmccright
11-22-2006, 11:40 AM
I'll check the torsion bar insulators thanks. Just odd that it would start after did all that work...perhaps something not quite seated correctly.

I also tried to grease the lower ball joints (which are new) as recommended by BlazerLT, but the grease squirts out of the rubber boot's upper seal, wrapped by wire, as if the wire is not tight enough to keep a seal. Does this mean the joint is bad? If so, at least they're easy to replace. great ideas!

BlazerLT
11-22-2006, 01:11 PM
The thumping is probably the brake pads not being properly secred to the caliper or, the shocks.

Rock the truck back and forth and listen from the outside of the truck.

My poly sway bar bushing weren't tight enough and had a knocking for some reason. Had to take them back for GM stock rubber mounts.

jdmccright
12-05-2006, 02:53 PM
Yet another follow-up:

I retorqued all the suspension bolts with a recalibrated torque wrench and neither clunk has been resolved. I even found my right lower ball joint-to-arm bolts loose, one of them loose enough to have the lock washer uncompressed. Wondering if that could have caused early ball joint failure.
I've mentioned in another thread that the lower joint boots don't seem to fill up with grease, even with the truck raised off the front tires...it just squirts out in between the boot and the ball joint body where the wire is looped around the top to seal it up. I may replace both lower joints and try again.

I'm also noticing that the inner front brake pads do not align properly with the disc. They ride about 1/16" to 1/8" higher than the outer pads, resulting in uneven pad wear...a tiny sliver of the pad doesn't touch the disc at all! So, between those two things and possibly torsion bar slop, I'm at a loss. If this is something anyone else has experienced, I'd appreciate the responses. Thanks!

BlazerLT
12-06-2006, 01:33 PM
If grease is squeezing out, the balljoints are not your problem.

Also check your shocks. A shock that is blown will knock as well.

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