popping/clunking in front while braking

[Wxman2000]

I have been experiencing a clunking/popping noise in the front (passenger side) lately. It only occurs while braking, and even then it is not consistent. It only seems to happen when I'm on the brakes lightly, such a riding the brakes a little in a parking lot or something like that. If I am on the brakes harder, it doesn't happen or it stops. This also doesn't happen just driving down the road or while going over bumps. I had my Blazer in a while back for other work and the mechanic thought that the popping sound that I've described (he drove it too and heard) was that the rotor was warped. They removed the front passenger wheel and put it into drive on the hoist and played around with it and noticed that the rotor was a little warped and they think this was causing the popping sound. I had them take a look at the ball joints along with everything else, and it all looked OK...so this was their diagnosis.

I'm just wondering if that could be the case, it sounds pretty bad when it happens and I'd think it were a more serious problem that something like that...is this something anyone has heard of before, or does it sound like it may be something else? Thanks.

[s10blazerman4x4]

It could be the rotor because i dont think a warped rotor is a good thing.I know i had a sound such as that but mine turned out to be i only had one bolt holding in my drivers side caliper and it would hop around when braking and make a god awful sound. My 2 cents, I know what could be coming for a reply but will hold off till more knowledgable people chime in.

[BlazerLT]

Originally Posted by Wxman2000

I have been experiencing a clunking/popping noise in the front (passenger side) lately. It only occurs while braking, and even then it is not consistent. It only seems to happen when I'm on the brakes lightly, such a riding the brakes a little in a parking lot or something like that. If I am on the brakes harder, it doesn't happen or it stops. This also doesn't happen just driving down the road or while going over bumps. I had my Blazer in a while back for other work and the mechanic thought that the popping sound that I've described (he drove it too and heard) was that the rotor was warped. They removed the front passenger wheel and put it into drive on the hoist and played around with it and noticed that the rotor was a little warped and they think this was causing the popping sound. I had them take a look at the ball joints along with everything else, and it all looked OK...so this was their diagnosis.

I'm just wondering if that could be the case, it sounds pretty bad when it happens and I'd think it were a more serious problem that something like that...is this something anyone has heard of before, or does it sound like it may be something else? Thanks.

You don't use the search mcuh do you.

How about looking at the top of this section:

http://www.automotiveforums.com/vbul...d.php?t=302656

[Wxman2000]

Yes, I do and I've done an extensive search. I've already checked into the fix you've referred to and this is not the case. I understand this situation sounds similar, however, this is not the case.

[Rick Norwood]

Originally Posted by Wxman2000

I have been experiencing a clunking/popping noise in the front (passenger side) lately. It only occurs while braking, and even then it is not consistent. It only seems to happen when I'm on the brakes lightly, such a riding the brakes a little in a parking lot or something like that. If I am on the brakes harder, it doesn't happen or it stops. This also doesn't happen just driving down the road or while going over bumps. I had my Blazer in a while back for other work and the mechanic thought that the popping sound that I've described (he drove it too and heard) was that the rotor was warped. They removed the front passenger wheel and put it into drive on the hoist and played around with it and noticed that the rotor was a little warped and they think this was causing the popping sound. I had them take a look at the ball joints along with everything else, and it all looked OK...so this was their diagnosis.

I'm just wondering if that could be the case, it sounds pretty bad when it happens and I'd think it were a more serious problem that something like that...is this something anyone has heard of before, or does it sound like it may be something else? Thanks.

When I had warped rotors on the wife's van, there was no mistaking it. All I had to do was take the van up to approx. 65-70 mph and step on the brakes pretty hard. The shake from the front end almost caused us to loose control of the vehicle it was really bad. I pulled the rotor off and had it checked before we trued it up and it only had .005 runout. This was a brand new rotor right out of the box from Autozone. Once a light skim cut was made on the rotor the problem was gone. If you have a warped rotor try this test. A skim cut on a warped rotor is fast easy and cheap. If your garage suspected a warped rotor, they should have fixed it.

[Wxman2000]

I tried the above test of braking quickly to see if there was any reaction...doesn't appear to be the problem that you had. There's some slight vibration, but nothing severe, not that I felt I could lose control of the vehicle or anything.

Just for fun, even though this sound wasn't occuring while driving over rough roads, I also replaced the hood washers described in the other post and it did nothing to alleviate the clunk/pop sound. Again, this only seems to occur while driving at slow speeds (less than 20mph) and when I first get on the brakes, there is no sound if I'm simply driving along at 20mph.

Any other suggestions to what the problem might be or other things to check? Thanks.

[Rick Norwood]

Originally Posted by Wxman2000

I tried the above test of braking quickly to see if there was any reaction...doesn't appear to be the problem that you had. There's some slight vibration, but nothing severe, not that I felt I could lose control of the vehicle or anything.

Just for fun, even though this sound wasn't occuring while driving over rough roads, I also replaced the hood washers described in the other post and it did nothing to alleviate the clunk/pop sound. Again, this only seems to occur while driving at slow speeds (less than 20mph) and when I first get on the brakes, there is no sound if I'm simply driving along at 20mph.

Any other suggestions to what the problem might be or other things to check? Thanks.

The only other thing that I'm thinking of is to check and make sure that the brake calipers and pads etc. have all been installed correctly. Did they replace the calipers?

I think what you might be hearing is the caliper "rocking" or clunking up and down in its position when the brake pedal is depressed and released when rolling. Here's what I mean. If your caliper assembly is working and you are going forward and press the brake pedal, the caliper should be all the way forward in its "cradle" but if you shift into reverse, the caliper might clunk as it moves within what ever slop is built into its cradle. Then, the next time you shift into drive and go forward again, the clunk is heard from the caliper returning to its original position. This happened to My wife's van. Again, check to make sure everything is installed correctly.

Did you have any other work done when you took it to the garage? I would take this truck back in and complain about the noise and have it checked out immediately.

[1996LTOwner]

Have you noticed if it tends to happen more when the wheels are turned? My 96 LT was clunking horribly, especially when I'd turn the wheel to one side or the other and would put in in gear or just after starting to move. After replacing the drive axles, shocks, ball joints, idler arm and upper control arm bushing the clunking became much less frequent but can still be heard when turning sharply when backing out. One day while under the truck, I noticed a wear mark on the front of both of the lower control arms. With both front wheels off the ground, I had a friend turn and hold the wheel all the way to one side. By grabbing the tire and pulling it, I was able to get the steering knuckle to contact the lower control arm. The only flex I could see was in the inner tie rod end on the passenger side. I had it checked by the shop and they said that the tie rod end doesn't need replaced. The wear marks appear to be on what looks like wear pads of some sort. Each lower control arm has a small round piece of rod that was welded right where it is contacting it. Now, it happens so infrequent and I know what is causing it, I accept it as it"s just a Blazer thing. Hope this helps.

[westsider]

This is the exact same problem my car is having except my clunk noise is coming from the drivers side. I have not been able to figure it out but I am sure it has something to do with the brakes. I will let you know if I fix it

[[RIT]IVIr_Evil]

Having similiar problems.. I relplaced all front and rear rotors and brake shoes on my 99Blazer (Disc Brakes on all 4). Now I have a huge problem when breaking the truck makes the clunking or pounding noises and the ABS activator is set off as if the truck thinks its sliding on ice or something. I heard there were lots of recalls on this ativator thing?? Not sure though... The guy at Midas wouldn't attempt to fix my problem cause he said it is only a GM fix and stated to check out the recalls.. I believe my front driver side caliper is not working properly causing my driver side front brake to stick. I think this is causing the truck to think that it is sliding on ice and causes the activator for the ABS to start and then causes clunking noises.. Not sure though.. just my guess.. or the sliders are seized up and need to be unseized (had to do this to my rear disk brakes) - hope this gave you some ideas on some stuff to check out - - tom

[joeuser742]

I have a 98 Blazer and have the same clunking problem, when I turn the wheel all the way and start to move, there is a very loud clunk. I'll be getting under the truck this weekend to replace the rear main seal, and will also check out what's going on with the popping noise. I also have changed all the ball joints, idler arm, pitman arm, tie rod ends and shocks. All this stuff was needed. The only thing that I haven't changed were the bushings, which I will be doing this weekend, and taking a look at the spring bar to make sure that's not moving.

[[RIT]IVIr_Evil]

I haven't had my truck looked at yet.. but I know my abs activates by its self now with out me even pushing the brake!! I am going to take it in when I have the money which is sometime after Nov 18th..
-Tom

[joeuser742]

Well, I replaced the rear main seal that weekend and took longer than I thought. Recently, I finally got to changing 2 of the 8 bushings, I need to buy the removal/install tool for the rest. The rubber on all of them are cracked. I'll probably get to the rest of them last week of December.
As for the ABS activation at low speeds, I remember seeing something about that. I can look it up if you want. I think that the dealer just changes the wheel speed sensors and cleans out the stuff that gets trapped in there. Something like the gap gets too big between the sensor and the teeth.

[[RIT]IVIr_Evil]

Originally Posted by joeuser742

Well, I replaced the rear main seal that weekend and took longer than I thought. Recently, I finally got to changing 2 of the 8 bushings, I need to buy the removal/install tool for the rest. The rubber on all of them are cracked. I'll probably get to the rest of them last week of December.
As for the ABS activation at low speeds, I remember seeing something about that. I can look it up if you want. I think that the dealer just changes the wheel speed sensors and cleans out the stuff that gets trapped in there. Something like the gap gets too big between the sensor and the teeth.

Yeah I went in and explained the problem and asked about the sensors and the dealership stated that it only had two sensors which I thought there were two main ones and then 4 lil ones in the hubs?

anyway.. prolly be gettin it fixed soon..

-tom

[whyme]

it is your torsion-bar moving around in your lower a arms,you could try shotting a good lubricant in your lower a-arms were the torsion bars contact the a-arms,(i did but it got worse????)this LOUD clunk was most noticeable pulling out of a driveway with the steering wheel cranked over to one side or another,i'm still working on it by spraying one type of oil or another into the a-arm.......