toyota4x4907

Is this about of drag on the brake disk normal? I couldnt keep it spinning. As soon as I quit pressing on it, it stopped.
http://s286.photobucket.com/albums/l...t=Yotas020.mp4
I pressed the pads back just a little. They moved just a hair, and it seemed to be able to spin more freely.

scope103

Disk brakes are intrinsically self-adjusting, so that amount of drag does not seem out of line. You might inspect the dove-tails that the calipers move on to be sure they are not "too" rusted. If they rust up, the cylinder may retract the tiny amount necessary to release that pad, but the opposite pad may continue to press against the disk. You said you moved the "pads"; as long as you didn't have to push too hard to do that you're probably okay.

sb5walker

x2 on cleaning the tracks and pins that the pads slide on, so that when hydraulic pressure is released, pads are free to move back a little bit. I usually periodically spray the tracks with a rust converter after cleaning thoroughly, and replace the pins when they begin to rust.

But there will always be a certain amount of drag on disk brakes since, unlike drum brakes, there are no springs on the friction material to pull it back when the brake pedal is released.

xxxtreme22r

Also make sure the caliper pistons are not staying out and at least returning somewhat. I had to basically take my calipers apart and pretty much rebuild them the last time I did my brakes because the pistons were rusted and gunked up pretty good not allowing them to retract a little.

I cannot remember if we are or are not supposed to use the shims that come in the brake pad kits. I did not use them on mine and have had no problems.

But like the others have said, you will always have some drag on the rotors. And if those pads are brand new they will loosen up some as they wear.

James Woods

iTrader: (1)

If you are talking about the shims that you put on the back of the pads, those are just to reduce any noise and make no difference on performance.
Like others said, disc brakes will always have some drag on them, they will never spin like a bicycle wheel. If you don't see any signs of excessive heat, like warped or blued rotors, than its probably not something to worry about.

xxxtreme22r

That's what I thought, thanks James.

toyota4x4907

Thanks guys. I've never dealt with brakes before. The brakes (calipers, rotors, pads) were replaced about 2000 miles before I bought the rig, so they have about 20K miles on them. Arent they supposed to last 40K-50K? CAnt remember.
Anyways, I was thinking more along the lines of the pistons not retracting far enough. Like I said, I have no idea how far they should be retracted. When looking at the caliper through the pad slot, I can see where the pistons are... I'll try to take a picture in a few minutes.

sb5walker

The pistons don't really retract - there's nothing to do that unless the rotor is warped. They may get nudged back a bit from normal vibration, and for that to happen it is important that the pistons move freely, as xxxtreme22r mentioned. I will say that if you have the four piston calipers, that they are some of the best calipers I've ever worked with on any vehicle and work very well for an amazing number of years and miles with very little servicing. Nothing lasts forever, tho.

xxxtreme22r

yeah I guess retract/return was probably a bad term, hopefully he understands what I was trying to say though. Unfortunately for use the whole caliper is bolted on the knuckle instead of actually floating like most of the other vehicles I have had.

wvboy

I'm having a similar issue, I ordered calipers today. My left front is dragging a bit and is hotter than the right after driving home from work (50 miles) so I'll put both calipers and a new set of pads on just to prevent any future problems.

I noticed a slight pull when coming to a stop, almost like a low tire, and when checking it out I could feel the heat difference on the front wheels.