Rear brakes how do i get the pistons to retract all the way

Try opening the brake bleeder. Some foreign models have a screw in the rear of the caliper that retracts the piston.

Hi, if this is a front caliper that is still on the rotor, I pry between the rotor and rear brake pad to push the piston in. I usually have to pull on the caliper a bit to get it retracted enough to get a screwdriver in between. If the caliper is already off the rotor, I leave the old inside pad on the piston and put a large c-clamp over the caliper to push on the pad and retract the piston. If this is a rear disk caliper or if you have any questions, please reply.

Clockwise-on the rear
I would open the bleeder valve first, push piston in,then screw parking brake in.
You need to flush your brakes every couple years,anyway.
After you install new pads,ratchet brake up by hand.

If it's like the 2003 The left-hand brake caliper piston retracts counter clockwise and the right-hand retracts clockwise.

One side,turns right,and push in slightly,and the other side turns left,to retract.

If you are replacing the rear pads and are trying to retract the caliper pistons here is what you need to do.
Use a piston installation tool in order to twist the brake caliper piston into the brake caliper bore.
If you do not have the tool you can retract the piston by using a needle nose plier.
Exert downward force and rotate clockwise until the piston bottoms out.
Before installing be sure the two "U" shaped slots are at 6:00 and 12:00 Oclock.

yes, you need a piston retract tool for the rear cylinders. rear piston must turn clockwise as it is being retracting.

usually with a special tool you can borrow at autozone. because the rear brakes are usually the parking brake. you have to screw them back in. if there is a cross pattern or some type of groove in the piston will confirm this.

With rear brakes the caliper piston must screwed in. It usually has a parking brake mechanism that has to screw out as the pad wears down. When you install a new fat pad, the piston won't retract with normal pressure of a clamp but must be screwed back in on the parking brake screw. This can be done with a long nose pliers but tools are made just for the purpose. I hope this helps.

If its the front brakes you are working on and the piston won't retract into the caliper then you need a new caliper, or both actually. Calipers need to be replaced in pairs. If you are working on the rear then you need a special tool to turn the piston back into the caliper. you can get the rear disc brake tool at any auto parts store. Turn the piston clockwise to retract it, and pay attention to the little spots cut out of the piston that the tool grabs to turn it. They need to be at the top and bottom of the piston once you fully retract it or the little pin at the bottom of the inside brake pad wont sit against the piston. And once again if it still wont retract then you need to replace both calipers. Once you are finished you need to pump up the brake pedal and then pull up the parking brake lever and release it 10 to 20 times to adjust the piston.