Help. I have to "re-lube" driver-front brakes every 3 weeks.

[TBMounty50]

I'm new to the forum but not new to brakes. However, this has me dumbfounded. My driver side, front brakes seem to push all the grease out from between the contact points of the pads and bracket on my '98 v8 AWD. when this happens I get an embarrasing grinding/groaning noise. It's not the typical squealing from vibration or the squealer tabs. I've tried two sets of rotors, three different sets/types of new pads, replaced all hardware each time, replaced the caliper bracket, pins, hose and rebuilt the caliper. The pads wear evenly and the brakes stop just fine although it walks the shims off the back after a while. I've also used three different types of brake lube as well. I will clean and lube the pads, put them together and they will be fine for about three weeks. Then I have to do it all over again. Only the driver front wheel is doing this and I've thoroughly bled the system several times. I've been doing this for almost a year. I'm getting sick of it. Any advice?

 

[waskly]

caliper pins worn or sized? or the caliper has too much play when installed? dunno most people dont check the anti queek once the break work.

 

[madbrad104]

wheel bearing out. does it make a growling noise? change wheel bearing

 

[RomeovilleIL]

If brakes are wearing normally then the caliper is not frozen. Losing antiseize or lube from the bracket would not seem unusual because that area is not sealed from the elements. Water will wash it away over time in normal driving conditions.

wheel bearing out. does it make a growling noise? change wheel bearing

I agree. Sound is coming from somewhere else besides the brake. In that area the hub is most likely answer. You can dissasemble and inspect. If in doubt, swap hubs to opposite sides of vehicle and see if problem travels with it.

 

[TBMounty50]

I agree with the washout, but every three weeks? And only on the driver side? That was my reasoning behind trying different types of lube. Maybe one would be more resistant to washout....they aren't. I've replaced both front hub assemblies, each less than a year ago. It was easy to pinpoint the problem when they started to go. That's not the noise I'm getting. Once I tear them down, clean and lube them, the noise is gone for 3-4 weeks. Then they start to make noise every few stops and within a couple days they are making all kinds of racket on every stop. This is mainly at slower speeds like stopping from 35-0. Tear down, clean, lube, noise gone, noise reappears in 3-4 weeks, repeat. Of course I've replaced all those parts stated earlier along the way. Now I'm done replacing parts and simply 're-lubing' untill I figure out what is causing this. I was also thinking too much play in the caliper and that's why I replaced the bracket with one from a parts truck. Also, I cleaned the pin bores thoroughly and loaded them with grease. Then I used a c-clamp to force the pins into the bores, displacing the extra grease out and into the dust boots. This really took alot of the slop out of the pins and I thought for sure that was going to fix it. I was wrong. Any way that a problem in a hard line or ABS system is the cause? There are no stored ABS codes. Thanks for the insight so far guys, it's just that with this problem, I've been there, done that...and I'm tired of doing it. Help!

 

[RomeovilleIL]

Is there any pulsing or shudder to accompany the noise when braking? Is it possible that the rotor is not staying solidly seated? When you take the tire off and then reinstall everything it retightens everything but then works loose again? Is it held in with retainer nuts or just tire pressure and lug nuts? Suppose that would be very easy to test by waiting till the noise starts, taking tire off and putting back on without touching the brakes themselves to see if noise is uninterupted.

A second thought... You mentioned that the caliper was rebuilt. Is it possible that the rebuilt one is not working properly, such as moving too far in-out as brakes are applied and released as opposed to the usually not moving back in enough and causing drag? Just a thought. Calipers aren't terribly expensive so a rebuild saved like $20.

Last thought... Have you noticed any fluid loss? When you are doing the repairs, do you open the bleeder and compress the piston allowing fluid out then top off, or are you keeping the system closed and pushing the fluid back up the lines? Maybe there are contaminents other than air in the lines.

 

[TBMounty50]

There is a slight shudder, probably from a little warpage but it's there all the time and not just when it's acting up and it's barely noticeable. I'll try the R&R on the wheel next time but nothing ever turns up loose when I tear it down.

I rebuilt the caliper that was on it, even though it showed no signs of needing it. The kit was only 8 bucks so it was a cheap attempt to solve the mystery. Once I got it torn down, the pistons and bores were clean as a pin and no other apparent signs of damage, so I went ahead and put the new stuff in. It doesn't seem to drag, the pads wear evenly and it doesn't pull to one side under braking, so I guess it's working ok.

Not sure what you mean about the bleed sequence. I remove cap on master, assistant pumps up pedal and holds, I crack bleeder, close bleeder and signal to helper that it's ok to release pedal, repeat as neccesary while monitoring fluid level in master. I've bled them so much that all the old fluid/contaminants should be displaced by now.

 

[madbrad104]

ok have you changed the rubber lines yet? possible collapsed hose? i put aftermarket drilled and slotted rotors on my exploder from summit when i had front brake issues haven't touched them yet after 40k its a good investment cause theres to much heat from braking on these trucks causing warpage and hot spots on the rotors

 

[TBMounty50]

Yes, only on that side and it was a shot in the dark. There were no other signs that it was collapsed. Drilled/slotted rotors and new pads was the first thing I did when it first started this problem. Now I'm back to standard rotors. The problem is the same with both sets. I've tried both ceramics and semi-metalics.

 

[OneLever]

Suppose that would be very easy to test by waiting till the noise starts, taking tire off and putting back on without touching the brakes themselves to see if noise is uninterupted.

I agree that you're probably tracking down a problem besides the grease between the brake pad and bracket. Each time you go in to re lube them you're doing other things too. One of those other things is helping to mask the real problem for a short while after.

 

[budwich]

when your problem comes back, take your tire off, put a few lug nuts back on then have someone put some braking force on the pedal, then either wrench the wheel hub nut or "lever" a couple of the lugs to turn the wheel and observe what's happening. IF you are lucky you will get an idea of what's happening "exactly".

 

[TBMounty50]

CV axle on same side I'm having problems with just bit the dust yesterday. I replaced it today with a used spare I had(convenient!). Anyone think it may have been contributing to my brake issues in any way? I don't really see how it would but it would be nice if I just eliminated the problem.

 

[OneLever]

I get an embarrasing grinding/groaning noise. ...I've been doing this for almost a year. I'm getting sick of it. Any advice?

It could very well have been the source of your grinding noises. CV-joints can sound like that as they're going bad. I'm just surprised it took that long for it to completely go.

 

[RomeovilleIL]

Creates an interesting question - why would the CV go silent for extended periods after the front end was lifted and tire removed? I would think the noise was constant unless you did something to the CV when working on the brakes. You don't by chance have a 2-3" torsion lift?

Guess we'll have to see if the noise comes back or not.

 

[OneLever]

I've noticed that simply jacking up the front end causes a dramatic increase in the angles of the half shafts. This would be enough to shift the interal parts of the CV-joint around a bit. Perhaps repositioning the bad bearing enough for awhile.

Here's a great link by Turdle on CV-joints, mainly because their just plain cool: Link

 

[CDW6212R]

I'm not sure what grease you are dealing with that is exposed to the air, but nothing on the 95-01's needs any grease added ever to the brakes.

The calipers do have sealed boots on the slide pins, which should have adequate grease inside them. If you never remove those pins, or the boots, those calipers can last the life of the vehicle.

If you do open those boots up and expose the greased internal area, then that dramatically increases the wear of those pins. Never remove those caliper bolts, only remove the two larger bolts at the spindle/caliper brackets.

If those caliper pins have been exposed to the air(grease visible or added or wiped off), replace the caliper. Note that rebuilt calipers may very well have worn pin bores, which is what you are trying to avoid. If those pins and the bores are kept sealed by the boots, they can last for ages. If they get opened up, then any slightest debris will begin to wear out those pins/bores. That creates the possibility of the caliper moving beyond the proper range of motion. That could be the source of your noises.

My 98 truck had 150k miles on it when I began doing custom brakes for it. They never made any odd noises. My 99 Explorer has 154k on it now, with the original calipers. Both of my trucks have been used to deliver mail, I know brakes. Good luck,

 

[TBMounty50]

Not sure I understand. The pins fit into bores in the caliper bracket and the caliper bolts to the pins. The original pins were nearly dry so I cleaned the bores very well and lubed them liberally with synthetic grease and installed new boots. You're right, otherwise I would have had no reason to remove them. The grease in question is applied to the stainless hardware where the steel backing of the pad touches the bracket.

I only tweaked torsions a little, about 3/4 inch of lift. The CV started making grinding noises the day before it caused the steering wheel to wobble and feel like it was tracking groves in the road. The grinding did start/stop as speed and steering input changed. This was a different noise than from the brakes. Plus the brakes only made noise when I applied them. I didn't get any clicking or anything from the axle, even at full lock. Maybe vibration/harmonics from a slowly dieing CV joint? Like I said before, don't really see how that could cause it, just grasping at hope. Guess I'll find out in 3-4 weeks. All the advice is greatly appreciated too.

 

[CDW6212R]

I'd say that the CV axle was about gone when you lifted the truck some. The axle wouldn't have lasted much longer at the stock height. Don't worry about the next axles, it should take at least 2.5"+ to affect their lifespan. I have had my 98 truck over 2" lowered for 75k miles, on the same axles.

If you had to deal with those caliper slider pins, I would suspect that the bores are worn slightly. Any wear in those allows the caliper to move out of the proper range of motion, which can produce odd symptoms like your noises. I'd replace the calipers with rebuilt units, there's a decent chance those will be better. A lot of calipers will be turned in to rebuild because of those pin bores, so it's not a foolproof solution. Regards,

 

[TBMounty50]

I'm still confused Don. The calipers only have bolt holes that mount to the caliper pins themselves. The pins are inside bores in the caliper bracket. Unless you are refering to the piston bores inside the caliper. I mic'd these when I tore the caliper down and they were perfectly round, so I went ahead and rebuilt it. I tried two other used brackets and two "rebuilt" brackets from parts store in attempt to tighten the clearance between pin and bore because I was also thinking too much caliper movement. The "rebuilt" ones had more slop than the other three! Granted only one bore on each was that loose, the other being pretty snug. I used the same, brand new pin to check all bores to try to "feel" which ones were tighter. I also used digital calipers to confirm what I felt. I'm currently using the one I felt was tightest and returned both of the rebuilt units. Anyone know what the diameter of the bore in a new bracket is supposed to measure? I can't imagine that manufacturing tolerances would be as loose as what I've measured with these brackets, so I assume they have to be worn.

 

[CDW6212R]

I'm still confused Don. The calipers only have bolt holes that mount to the caliper pins themselves. The pins are inside bores in the caliper bracket. Unless you are refering to the piston bores inside the caliper. I mic'd these when I tore the caliper down and they were perfectly round, so I went ahead and rebuilt it. I tried two other used brackets and two "rebuilt" brackets from parts store in attempt to tighten the clearance between pin and bore because I was also thinking too much caliper movement. The "rebuilt" ones had more slop than the other three! Granted only one bore on each was that loose, the other being pretty snug. I used the same, brand new pin to check all bores to try to "feel" which ones were tighter. I also used digital calipers to confirm what I felt. I'm currently using the one I felt was tightest and returned both of the rebuilt units. Anyone know what the diameter of the bore in a new bracket is supposed to measure? I can't imagine that manufacturing tolerances would be as loose as what I've measured with these brackets, so I assume they have to be worn.

I think you have identified the problem. I keep telling people not to loosen those "pin" bolts. It is likely most of the rebuilt calipers will have those same larger(worn) pin bores.

I don't know what the bore sizes should be. If you do think that is your problem, and the others were worse, I'd go to a salvage yard and find the best pair I could get there. Try to find one that looks like the front brakes haven't been abused, rotor color, high mileage, painted calipers, aftermarket parts.