How much disc brake drag is acceptable?

jeep
maintenance
cherokee

#1

My front disc brakes are creating a small amount of drag on the rotor. With the car jacked up and wheel off I am able to easily turn the rotor by hand, but there is a small amount of drag. I haven’t had any problems with my brakes, they have never frozen or overheated, etc. I put new brake pads and rotors on the front about 6 months ago only because it was time for replacement.

The question is: how much disc brake drag is acceptable?

Looking around on the internet for answers there doesn’t seem to be a consensus: some people say absolutely no brake drag, some say that a small amount is normal.

What do you think?


#2

It’s normal for the brake pads to slightly drag on the rotors. If you can turn the rotors freely by hand nothing’s wrong.

Tester


#3

A car wheel will not spin freely, like say a bicycle wheel lifted off the ground. As long as you can spin the tire without a big effort all is fine. As soon as you release your hand from the spinning wheel it will stop spinning quickly.

If you can spin the tire with one hand, it is likely fine. If it takes two hands and some effort then check for something binding.


#4

The pads are touching the rotors, so a small amount of drag is normal. As long as you can turn the rotors by hand there’s not too much drag.


#5

that was also my problem to my brake disc before and i must agree with you. There is some slight drag on the rotors which is normal.


#6

After you’ve been driving for a while, feel each wheel near the brake disc. Very hot indicates brake drag.


#7

A small amount is not abnormal, but it should be very slight.

The only thing pulling the pads back away from the disc when you let off the pedal is a gasket called a “square cut “O” ring”. The ring is in a groove around the piston. It distends slightly when the brakes are compressed and when the hydraulic pressure is removed it returns to its resting shape, a shape much like a large faucet washer. That return to shape pulls the brake’s piston slightly back from the disc, relieveing the drag. However, the travel is slight. It can leave a slight drag. One good test is to compare the drag on one side with the drag on the other. If there’s a significant difference, than a problem exists. It’s rare forboth side to stick at once.

I tried diligently to find a good diagram on the internet but was unsuccessful. Sorry. I hope my verbage is enough.