Rear Driver Side disc brake dragging (1 Viewer)

[Alexstang9]

Hi all, I posted this forum a while back and the replies I got were pretty helpful so I figured I would try again .

I have been on a budget quest to drive my mom’s old 94 cruiser across the continent again. However, recently, I noticed my rear driver side disc brake was getting scarred by the pad.

When I was first getting the old girl running after a 10 year hiatus of sitting in the garage, I had found an old tech note from a garage saying that rear calipers had to be replaced. At that time, the calipers were not dragging and seemed to function properly.

Over the last several thousands of miles, the caliper seemed began to stick and cause the pad to become a sanding block for the rotor.

There were and are no leaks in the system, so I replaced both rear calipers, rotors, pads, and slide pins, and spending over an hour bleeding the system. I did forget to bleed to the LSV (probably the source?). The caliper at this point is brand new with new fluid and still dragging. All the other calipers work perfectly except this one. The brake pedal feels normal if not a little soft when the engine is turned on.

I’m going to be looking around the surrounding area this weekend to see if there is any rust keeping and parts from moving freely. At this point I’m not sure where to go from here, I just want my baby back on the road

 

[BILT4ME]

Check your wheel bearing play on that wheel. It is possible the wheel bearings are loose, causing brake drag.

Otherwise, change the brake hose.

Did you move the rod for the LSPV all the way to the top (disconnect and raise to the body) to allow the most free-flow during bleeding? That will do a better job of getting air out of the brake system.

Yes, air in the line CAN cause it to drag as the gas expands from heat, pushing the piston out.

 

[ppc]

Good suggestion to change the brake hose. My neighbor had front wheel drive Dodge that kept having failures (3 times) every 6 months of the rear hub bearings where the diagnosis being a frozen caliper. After reading about a similar problem and solution, on this forum, where the rubber brake line failed internally preventing the release of brake pressure on the caliper, I suggested replacing the brake line. BOOM - no more failures.

 

[Alexstang9]

Thank you both for the replies, I’ll have try that this weekend, but I do not think I was 100% accurate with my description.

I tried driving the truck last night again to make sure I was describing it right and this time the caliper sounded like it was grinding the pad again but it was sounding like the it was pulsating, but still grinding.

I’m going to to change the rubber hose and see what happens.

 

[ZackR]

Thank you both for the replies, I’ll have try that this weekend, but I do not think I was 100% accurate with my description.

I tried driving the truck last night again to make sure I was describing it right and this time the caliper sounded like it was grinding the pad again but it was sounding like the it was pulsating, but still grinding.

I’m going to to change the rubber hose and see what happens.

If you are going to change one I'd change the rest as well. I had a OEM rubber hose (original to 94') fail about a year ago. The hoses are old and worn out at this point.

 

[Alexstang9]

If you are going to change one I'd change the rest as well. I had a OEM rubber hose (original to 94') fail about a year ago. The hoses are old and worn out at this point.

On my way to pick them up now!

 

[BILT4ME]

On my way to pick them up now!

There are (7) total.

 

[Alexstang9]

Update**
I just changed all the hoses, bled the system again, and still making the pulsating grinding noise.

I’m now starting believe something else is afoul, namely the wheel bearings. With the wheel up in the air, I am able to spin it and recreate the grinding noise if I spin fast enough. However as I jack the truck up, I do not notice a change in camber of the wheel.

This one really has me stumped.

 

[BILT4ME]

Update**
However as I jack the truck up, I do not notice a change in camber of the wheel.

This one really has me stumped.

That's because it's a solid axle truck. The camber doesn't change when the suspension goes up or down.

 

[BILT4ME]

Update**
I just changed all the hoses, bled the system again, and still making the pulsating grinding noise.

I’m now starting believe something else is afoul, namely the wheel bearings. With the wheel up in the air, I am able to spin it and recreate the grinding noise if I spin fast enough. However as I jack the truck up, I do not notice a change in camber of the wheel.

This one really has me stumped.

Have you checked the fluid levels in:
Front Differential
Rear Differential
Transfer Case
Transmission
Engine
?

Is the noise you felt on the FRONT or REAR axle?

 

[Alexstang9]

Something else I just noticed, the sound is only present when driving forward.

 

[Red Merle]

Something else I just noticed, the sound is only present when driving forward.

I would dig into the wheel bearing idea and then swap out the head gasket while you are in there, at least that is what I did.

That said, I probably could have held off on the head gasket if all I wanted was for the truck to roll quietly.

When was the last time you went through the front axle?

Could also be the parking brake shoe dragging in the rear.

 

[Alexstang9]

Before I embark on the wheel bearing quest, is it possible that the rotor is not completely flat? I bought the rotors at Advance auto as I was working on a more modest budget a few months ago but this time I didn’t think twice that maybe the cheap rotors might be a culprit.

All the fluid levels are topped off.

 

[Red Merle]

Before I embark on the wheel bearing quest, is it possible that the rotor is not completely flat? I bought the rotors at Advance auto as I was working on a more modest budget a few months ago but this time I didn’t think twice that maybe the cheap rotors might be a culprit.

All the fluid levels are topped off.

Can you pull the wheel off and spin the rest of it to see if it's rubbing? You should be able to get a look. You may have to pull the rear driveshaft from the rear diff, but that is no biggie, or get all four wheels off the ground to really see.

 

[Beej]

Does the sound happen when you are driving straight or when you are turning (or does that make a difference)?

 

[lazy]

When I finally got around to doing the hubs on my "grocery getter," I found out the source of the noise from my driver side rear. I did brake lines, calipers, pads, rotors and hubs all in one go, so I can't pin down what my real issue was.

 

[Alexstang9]

***Update

Swapped the pass side rotors just to test the theory it was the rotor, turns out it’s not a warped rotor as the rotor from the pass side which doesn’t make noise on its side does make the noise on the driver side.

While I was spinning the wheel off the ground I noticed that as the rotor spins, there is a slight wobble. I checked the back of the hub and all the nuts and bolts are tight.

I am next going to make sure wheel studs are as flush as possible as the wobble is slight. My worry now is that if everything else checks out, I might have a bent axle.

Again, thank you all for the advice!

 

[Alexstang9]

Does the sound happen when you are driving straight or when you are turning (or does that make a difference)?

Doesn’t seem to make a difference, the sound doesn’t happen in reverse only.

 

[Alexstang9]

Have you checked the fluid levels in:
Front Differential
Rear Differential
Transfer Case
Transmission
Engine
?

Is the noise you felt on the FRONT or REAR axle?

The noise is definitely coming from the pads/rotor rubbing on the drivers side rear.

 

[Red Merle]

The noise is definitely coming from the pads/rotor rubbing on the drivers side rear.

Sounds like a sticky caliper. You could try to rebuild it but I just went with the Napa Eclipse calipers. They are OEM Toyota rebuilds and are very nice parts.