Winding back Vauxhall Combo rear brake pistons

The correct rewind tool will turn and push the piston at the same time, do not use one that just pushes, it is not suitable for rear calipers, some calipers wind clockwise, some anti-clockwise, I can never remember which vehicle uses which, but it usually becomes obvious within moments. it is always better to let the excess brake fluid out at the bleed nipple rather than push dirty fluid back into the system. The bolt that comes with new pads is usually the one that holds the caliper to its bracket (yes, I know there are two each side, but non genuine pads come with just one for each side usually)

Thanks for the advice. Googling isn't being very helpful and I'm still none the wiser as to how they work. My simple mind would imagine some kind of ratchet mechanism on the handbrake which would have to be overcome to push the piston back. I'm sure the bolt supplied with the pads is the one that holds the handbrake mechanism to the back of the caliper so maybe the handbrake mechanism has to come off so I'm not fighting against it. Off to do my stint of ill mother nursing so this will have to wait until next week.

Google disc, not disk helps.

inside there is a threaded rod with a sort of spring loaded locking plate/nut which can move in orer to take up pad wear. Forcing the piston back will break the locking nut thing which is held with a circlip at the bottom of the piston bore. I have sometimes managed to repair them after animals have been at them, but replacement of the whole caliper is usual these days.

My wind back tool came with what they called a reaction plate with a hole in it which meant it had to be fitted on the tool and then the handle of the tool passed through from the inside of the caliper. The piston was so far out this was impossible. I saw another wind back tool in Halfords which had a slot. A few moments with an angle grinder and mine had a slot. Pads changed in a quite respectable time (for an amateur) with no problems.

And the wrinkly 89 year old Mum has made a remarkable recovery from pneumonia which means I'll have a bit more time to myself.

hurray, on both counts.