Main IndexAuto Repair Home Search Posts SEARCH
POSTS
Who's Online WHO'S
ONLINE
Log in LOG
IN









Search Auto Parts

1999 Chevy S10 ZR2 4x4 - Clunking noise from rear causing vechicle to buckle intermittently


  Email This Post



drew_doe
New User

Dec 16, 2014, 12:10 PM

Post #1 of 9 (1281 views)
1999 Chevy S10 ZR2 4x4 - Clunking noise from rear causing vechicle to buckle intermittently Sign In

 
I have 99 S10 4x4 with ZR2 suspension and 4.3L Vortec engine. The truck has over 200,000 miles on it and I have just replaced the front hubs about two weeks ago and everything is good there. Now, randomly when driving around 45-55 mph I will get a clunk noise that causes the truck to jerk a little. It seems to be coming from the rear of the vehicle almost like something locked up and then slipped free. This happened once a few months ago (prior to replacing front hubs) and then it has been doing it more frequently the past week. I would say it was about 3 times this week all in separate trips. Today it did it twice on my way home. Not sure where to start or what would cause this.


GC
User
GC profile image

Dec 16, 2014, 1:19 PM

Post #2 of 9 (1265 views)
Re: 1999 Chevy S10 ZR2 4x4 - Clunking noise from rear causing vechicle to buckle intermittently Sign In

Any way to safely get the rear wheels off the ground to spin them by hand? Parking brake shoes or hardware rolling around inside the hat, maybe? Do you see any metal shavings around those rear brakes? Might have to look in rear diff too.


____________________________________________________
Willing to help, willing to learn... Rob


Tom Greenleaf
Ultimate Carjunky / Moderator
Tom Greenleaf profile image

Dec 16, 2014, 1:38 PM

Post #3 of 9 (1263 views)
Re: 1999 Chevy S10 ZR2 4x4 - Clunking noise from rear causing vechicle to buckle intermittently Sign In

Good call Rob. OP - just anyway check out and clean up rear hidden parking brake which is a mina drum brake out of sight on rear disc brake models. Had to go looking and one did show this set up and they ARE a problem sometimes as they really can't expel any dirt, crap, moisture well and are not rubbing themselves clean like a plain drum brake kinda can otherwise but rather just static friction.


Couple models of full size and newer than this but GMs did have problems right away with hardware when new even but expressed that issue as no parking brake feel at all and find the left side shoe(s) tilted and all worn to crap losing position.


Now 200K later it would just be age and a thing most wouldn't ordinarily think of assertively checking unless doing regular rear full disc brake job with rotor off then notice it,


T



drew_doe
New User

Dec 16, 2014, 2:28 PM

Post #4 of 9 (1255 views)
Re: 1999 Chevy S10 ZR2 4x4 - Clunking noise from rear causing vechicle to buckle intermittently Sign In

Thanks guys, I planned on jacking it up tonight and inspecting it. At least now I have an idea of where to start. I will update with any findings.


Tom Greenleaf
Ultimate Carjunky / Moderator
Tom Greenleaf profile image

Dec 16, 2014, 2:51 PM

Post #5 of 9 (1249 views)
Re: 1999 Chevy S10 ZR2 4x4 - Clunking noise from rear causing vechicle to buckle intermittently Sign In

Hey - little time before I have to go. No waste in checking these out and not all that hard MOST of the time. Rob was probably spot on as I think you'll find a ground up mess inside and OK to just take all of it out as if that trashed now parking brake probably doesn't hold at all now but can drive (well not supposed to) without it for the time it takes to get parts if all AFued in there.


Just a hunch that the mess assorted junk at the speed you mentioned just might be able to all jam up, make noise and a funky drag which you said felt like a "buckle" feel whatever that means exactly.


If not real good looking and not the problem it would still be nice to check, dump out any junk and maybe tap off any lose rust if rotor is still nice and strong as it's a "static" brake meaning it's just friction while still not really meant to use while in motion but should be able to.


Old phart here, we called these of any type EMERGENCY brakes not parking brakes. I won't talk about driving a vehicle on public roads with just a parking brake while holding it released but sure did if moving cars/vehicles around if waiting on parts until another day it should work.


If not familiar with the idea just think of left and right sides as a mirror image of each other. A problem with one side means check the other too. Chance that friction material is separating from metal shoe too. Toss them if so.


Let us know what you find either way as I'm curious. Done with this crap long time now but if I owned that style would have it off and checked every other oil change at least,


T



drew_doe
New User

Dec 16, 2014, 4:37 PM

Post #6 of 9 (1238 views)
Re: 1999 Chevy S10 ZR2 4x4 - Clunking noise from rear causing vechicle to buckle intermittently Sign In

Ok so here is some updated info. On my way home tonight it was really acting up and maybe I'm dealing with more than one problem. It started with just the intermittent jerks I described above but progressively got worse. A few things I noticed that weren't happening before is my battery dummy light would illuminate when it was occurring in rapid succession and I was not hearing the noise in the rear. I forgot to mention earlier that I had to rewire the crankshaft sensor a while back, would a loose connection to that sensor cause it to jerk/lose power like this? It has also been raining here the past few days and has been very damp.


Tom Greenleaf
Ultimate Carjunky / Moderator
Tom Greenleaf profile image

Dec 16, 2014, 4:56 PM

Post #7 of 9 (1229 views)
Re: 1999 Chevy S10 ZR2 4x4 - Clunking noise from rear causing vechicle to buckle intermittently Sign In

Yes - This could be an quick engine fault that makes you feel like it's something else totally. Since you know what you did with wiring that would effect how or it engine runs and whatever you did to fix that it needs checking out PLUS why and what is up with a battery icon showing too - all one thing or just luck we/you don't know yet.


Check it all. Battery light is triggered when voltage isn't within spec. If wires and connections can cross up with each other who knows? It's wet you said. If only a plug in type connection WD-40 by it's name is supposed to displace the water. Then I suggest using dialectic grease on connection/plugged in items which is really a silicone grease that is impervious to dissolving in water AND doesn't conduct electricity on it's own but also prevents a wide range of corrosion too.


Back to workTongue


T


C



drew_doe
New User

Dec 17, 2014, 7:03 AM

Post #8 of 9 (1206 views)
Re: 1999 Chevy S10 ZR2 4x4 - Clunking noise from rear causing vechicle to buckle intermittently Sign In

Well I believe the issue was with the crankshaft sensor electrical connection. My previous repair job to the wiring itself was fine but the rubber grommet that keeps the clip firm to the sensor seems to have broke and fallen off at some point and needs to be replaced. There was a fair bit of play in the connection and I could reproduce the symptoms by barely touching the clip. So I have ordered a new one and time will tell if that was the problem but it seems to make sense at this point. I am still going to check out some of the other things you guys mentioned just for posterity sake. Great forum, thanks for the constructive pointers!


Tom Greenleaf
Ultimate Carjunky / Moderator
Tom Greenleaf profile image

Dec 17, 2014, 8:02 AM

Post #9 of 9 (1199 views)
Re: 1999 Chevy S10 ZR2 4x4 - Clunking noise from rear causing vechicle to buckle intermittently Sign In

If you can reproduce it just like that it must be the issue IMO. If splicing in a new connection there (glad you could find it) just do it right and do use that grease but know once greased it can be difficult if you get it on wiring near where you need to solder,


T







  Email This Post
 
 


Feed Button




Search for (options) Privacy Sitemap