Ive bought new discs and pads for my 7 kit, the discs are 10mm think and trying to fit pads into the calipers I can only get about 6-7mm gap between the pads where the disc should fit in. Ive tried pushing the caliper piston back on both calipers and theres no way! (and yes Ive tried a lot of force to get them back) Anybody else experienced this? Are my calipers seized, Ive had a completely wasted day in the garage today!

are the sliders seized

I don't know about Sierra rear calipers but on most other rear calipers you need to screw the pistons back, you'll not push them.

J

The rear (handbrake caliper) require the piston to be turned at the same time as pressing, to retract the piston and reset the handbrake mechanism. G-clamp and grips or angle grinder spanner will do it, with a bit of perserverance or there's a special tool. Once the pistons are back DON'T operate the handbrake lever untill you've pumped the pistons out with the foot brake.

Screw and push do not use force. handbrake actuatorlever must be fully released and returned against stop.


if you get a very cheap " brake cube" tool that fits on a 1/2" socket it makes things a lot easier.