I'm changing front brakes on my '04 S-type, 3.0 L, and have a stuck piston on the driver's side front. Only one of the two is stuck. I slowly depressed the brake pedal and one piston extended but the other is seated back, no movement.

How do I get it unstuck?? Help!! Thanks!

 

Are you sure it is stuck? It may just be that because there is no resistance that only one is moving but if you resist the moving one the other one will move. Try pushing the one that is moving back in and putting a clamp over it to hold it back and see if the other one moves when you press the pedal. Also don't press the pedal too hard as you may actually pop the piston out.
Hope this helps.

 

Pretty sure it is stuck as the old pads are beveled on the end where the operable piston is located.
I also thought about restricting the movement of the "good" piston in hopes the stuck one would move, but I need a bigger c-clamp.

If that does not work is there a caliper rebuild kit or do I have to replace the caliper?
Thanks!

 

You can probably get a rebuild kit or maybe even get a rebuilt caliper for a decent price. I would check auto parts stores or online.

 

Rebuilts are not too bad:

http://www.motorcarsltd.com/item.wws...p;sku=IN107415

http://www.motorcarsltd.com/item.wws...p;sku=IN107416

 

I DOUBT you have a stuck piston, they do tend to **** alittle bit and not push in, open the bled screw so you take out the fluid resistance and try to push in the piston then, just be sure and bleed that caliper when done or youll have a spongy pedal

 

Ahah! Piston was stuck and Badmojo had it right.

I went down to the local ACE Hardware and bought a 3" C-clamp; opened the bleed and pressed the extended one back in and leaving the clamp on, I applied the brake pedal slowly and the stuck piston popped out on the second push!

The new pads slid right in place; bled the air out with the help of the wife, and all is well!

Thanks for the suggestion Badmojo!