Hello all fellow boarders,
I just put on a brand new set of rotors because the drivers side front rotor was causing a out-of-round vibration when you were coming to a stop. After I installed the new rotor and put everything back together with the old pads and such, the wheel seems to have a really difficult time turning. It doesn't spin as freely as it should. What's the problem? Is it just because it has old pads that have worn against an out-of-round rotor?

concur with lawrence's post below, you likely have a piston that is perhaps not frozen, but is failing to retract. The only thing that makes the piston retract is the rubber seal around the piston. if the seal is stuck on a gunked up cylinder or if it has become brittle and hard, it will not retract the piston.

good news is the calipers can be overhauled easily, replacing the seals and dust boots. Clean out the caliper while you're at it. HIGHLY recommend you use QUALITY parts for this job. The seals and dust boots should not cost more than $10.

hope this helps

In addition to the other posts, you may want to check if there is a buildup of brakedust/crap where the outer edge of the rotor passes through the caliper. When I did mine I had to break away big chunks of the stuff with a screwdriver so the new (slightly wider) rotors could turn freely.

"Is it just because it has old pads that have worn against an out-of-round rotor?"

Did you keep the old pads? You would be best replacing them with new pads.

When you reinstalled the caliper over the new rotor, did you push the caliper piston back fully? You do this with the old pads in place using a screwdriver for leverage. You don't want to press against new pads or rotor as they can be damaged. Then install the new pads. The brake fluid level in the reservoir will go up as you push on the piston so keep an eye on it so it doesn't overflow.

If the piston can't be pushed back, it is seized and the caliper needs to be replaced.

Good Luck,
MORMIT
1985 245DL 230,000mi "Inga"
2002 S40 3,000mi "Sigfreid"

Did pistons go all the way back in? I suspect a frozen piston in one of the calipers.

Lawrence

Also make sure the pads travel freely on the caliper. Mine were warped and rusty and the pads would stick. I had to grind the edges of the pads to get them to fit properly. They work fine now. I didn't want to buy new calipers when the old one still worked OK.
Ben