How can I tell if my calipers are dragging?

[Hotwatermusic]

Took my front wheels off today to check my suspension and brakes, and noticed both wheel hubs took quite a bit of force to turn, more than I ever remember. The pads have plenty of life left in them and the rotors have a tiny lip on it, and I see no visible signs of misalignment or excess friction. I don't have a clear road long enough to do a coast-to-a-stop drive to check the rotors for heat, so I ask, how much resistance should there be on free turning brake rotors--and what are the signs of calipers sticking/dragging?

[sailchef]

Taking "quite a bit of force to turn" is a definate sign of calipers sticking.

There really shouldn't be any drag on the rotors. Calipers are designed to pull the piston back into the caliper body when the pedal is released. I would change out the brake fluid and bleed them in proper sequense. There may be air in the system that is keeping the pistons from falling back.

[Mattcamp]

You better check and make sure that the hub nuts aren't too tight. That would cause stress to your berrings and also make it difficult to turn. It might make you think that the brakes are dragging when it is something entirely different.

[g rad]

When I back out of my garage onto level ground,, one can tell if the moment before a costing stop,, is abrupt...a piston is not releasing,, I think that square section Oring actually rolls back with the piston, to release... that is how I tell... hope this helps.... Hayseed

[80-911SC]

if you have access to a hands free electric thermometer within 10 minutes of driving without abrupt braking you will have a noticeable difference in the temp of the rotors at each corner , if ambient temp is very low test very quickly as they will cool rapidly

[psalt]

Go for a drive then measure the rotor temps with an IR thermometer and compare side to side. A dragging caliper is obvious.

[LakeCleElum]

Stop on a slight incline and release the brake. If the car don't roll, you have issues. For me, it was the rubber hoses. Replaced those and I was golden; calipers were just fine.

[cbush]

I had a problem with this. One way I could tell was that one wheel always had a lot more brake dust. Of course the most obvious was the car would not roll on a slight incline. After I tried all the more expensive options I discovered the cause was the small metal clip that sits on top of the brake pads. It wasn't applying enough pressure to HELP push the pads back slightly after braking.

[911pcars]

If the tires are difficult to rotate (especially both), that's not normal. Check each brake hoses. They can fall apart internally and block the return of BF after releasing the pedal. However both failing at the same time would be an unlikely coincidence.

Could also be a blocked port at the master cylinder (swollen or deteriorated cup) or pedal (or MC piston) not fully releasing.

To confirm, open a caliper bleeder screw and see if there's residual pressure causing the pads to apply force against the rotor.

Sherwood

[Flieger]

The metal spring clip does not push the pads and pistons back away from the rotors, it is the piston seal which does this job.

[RWebb]

1st, I'd do routine maint. and see if that solves your problem:

if the brake fluid age is > 2 years or unknown; change it out

if the rubber brake hoses are 10 years old or unknown; replace with new rubber

the rubber hoses can also be palpated (unlike the steel braided one) & you will want to do this every year or so

- above need to be done periodically anyway; if problem persists after that, then
check the wheel bearing tightness and be prepared to replace MC; rebuild calipers; etc.

it will be easier to do the entire braking system at once, of course...

if I had to make a guess, I'd guess MC

- what are the rear wheels like??

- you can just -carefully - touch the rotors after a drive if you don't have an IR thermometer