Smoking Brakes

[FightinTXag]

Well, I discovered the noise that I thought was coming from the rear end was varying when I swerved left/right. So I changed front wheel bearings and spindle bearings.

While I was in there, I changed to manual hubs (which cured the grinding noise I had in 4wd).

I also had an issue with the truck drifting right when the brake was applied. So I put new calipers on both sides.

Now, when I drive the truck for longer than 5 min or on the highway at all, the left front brake starts smoking. The right front will do the same thing, but it takes a longer drive or more highway driving.

The drifting right seems to be cured though.

When I jack the front end up, the same spinning effort will send the left wheel around about 3/4 turn while the right wheel will go around 1.5 turns.

I drove around until the left front was smoking hot, jacked it up and the left front wheel didn't seem to have any more noticeable turning resistance than when it's cold. I cracked the bleeder, and fluid came out at a steady stream, and didn't seem to make the wheel easier to turn.

That leads me to believe the problem isn't the hoses, since relieving the pressure at the caliper doesn't seem to change anything.

Did I get bad calipers from Oreilly? Should I suspect my master cylinder?




Oh yeah, the front wheel bearings did fix the roaring noise I originally thought was coming from the rear end....

 

[zeroz400]

Did you put new pads in with the calipers? Maybe they're to tight and rubbing. If so your prolly going to be replacing your rotors. Check to see if your rotos have any blueing on them, its a sign of being overheated.

 

[FightinTXag]

I reused the old pads - they had plenty left in them.

But I'm pretty sure the pads are dragging. I'm certain too that if I continued to drive it like this, rotor damage would result.

I'd like to get the source of the dragging problem fixed though before I go evaluating any damage to the rotors.

 

[BowtieBlazer]

remove that caliper and grab the rotor at 3o'clock and 9o'clock pulling in-and-out towards you(you may even feel it with the wheel and caliper still installed....if so your bearings haven't seated all the way and are dragging, or you may have the wrong bearings installed, did you check them vs the old ones? replaced the races as well?

Check side to side that it looks like you have the same spacing between rotor and backing plate.

If it is indeed just the caliper grabbing its f'ed. I've bought a bunch of rebuilt calipers from o'reilly and never had a bad one. For next time if you buy new rotors get new pads as well, the pads "seat" to the rotors so new rotors may damage or warp if the old pads seated anything less than perfect wear.

Be sure when you are bleeding the system even though you never touched the rear to check it as well and push the proportioning valve reset button on the front crossmember.

 

[bigred81]

The problem with your frot brakes is the brake hoses are bod they are probably collasped on the inside not letting the brake fluid return to the master and it is draging so it is building heat to the point that it makes the piston in the caliper lock down on the rotor. A note always replace pads when this happens because it glazed the pad and it also cooks the pad to the point of being brittle maen it will fall apart any time it wants. Good thing to do is always replace the hoses and calipers in sets. Which means change both hoses and calipers at the same time so you get even braking power on both sides. Hope this helps.

bigred81

 

[FightinTXag]

The bearings are seated well. I did check that before I put the caliper on. I used the Haynes manual method (50ft-lbs, back off, 35ft-lbs, back off 1/4, lock nut at 190ft-lbs).

The bearings are correct, and I did replace the races.

If it is indeed just the caliper grabbing its f'ed. I've bought a bunch of rebuilt calipers from o'reilly and never had a bad one.

Since I've got the same problem with both fronts (left much much worse than right), I'd think the chances of getting two bad rebuilt calipers would be slim. But if it's ever gonna happen to anyone it'll be me.

For next time if you buy new rotors get new pads as well, the pads "seat" to the rotors so new rotors may damage or warp if the old pads seated anything less than perfect wear.

I'll keep that in mind if I end up having to get new rotors.

Be sure when you are bleeding the system even though you never touched the rear to check it as well and push the proportioning valve reset button on the front crossmember.

Proportioning valve reset button? Never heard of it. Maybe something I should check?

Could bleeding have messed up the master cylinder causing this issue? Read somewhere there's a rod you can adjust in the master?

 

[FightinTXag]

Ok BigRed,
I came dang close to getting the hoses too when I got the calipers since I know the pulling while braking issue can be caused by either calipers or hoses. But then I got the new calipers on and the pulling seems to have gone away and now I've got this new issue.

So I first suspected the hoses. But I figured if the hose was the problem then cracking the bleeder would cause a spurt of fluid and make the wheel free up some. But what you're saying about the caliper piston getting hot and seizing up makes sense.

I guess I'll start by replacing both brake hoses.

If the heat is making the piston seize in the caliper, could the caliper be damaged or could the heat have damaged caliper's seals? Those calipers have lifetime warranties, and if there's any question, I can pull them off take them back up to Oreilly and get two new ones when I get the hoses.

I'll check the appearance of the rotors and pads too.

 

[FightinTXag]

It's the bearings. I can't seem to get them adjusted correctly.
See my new thread:
http://coloradok5.com/forums/showthread.php?t=172583