So. I’m having to replace most of my brake system. I can’t find anything that says if the front brake caliper pistons, are different from the rears. Autozone, just sells one size of the replacement piston boots. I’m thinking, that the fronts, are a little bigger.
2005 G35X.
thanks!!!

 

You can buy rebuild kits directly from Nissan, or order the part online. They're not that expensive, you don't replace the pistons though, just the piston seals.

Why are you having to replace all your calipers though? That seems odd, they're not typically a component you actually replace unless there's a problem. Usually the calipers are good for the life of the car as long as you grease the slide pins thoroughly every time you change pads/rotors. You're on the stock floating calipers yes?

Racecar stuff you rebuild them every year (depends on use though) but that's due to the EXTREME heat from high performance brake pads. I usually take a file and nick a little groove onto the caliper bracket each time I replace pads on those kinds of vehicles just to keep track of when to rebuild calipers, every 5-10 sets of pad/rotor the calipers will get a rebuild but that's highly dependent on what type of track you're racing, road course and autoX will eat them up, straight line stuff doesn't because of the cooldown between hits. 1/8 mile you almost never have to do anything with the brakes and only the REALLY badass cars even need a parachute, 1/4mile has a lot higher trap speed though so a new set of pads might be needed each year but there's still not a whole lot of heat being built up in the brakes because you're pulling a parachute which does a LOT of the work for you. When your chute doesn't release though... those brakes are working hard.

Street car stock daily driver I never rebuild unless there's actually a problem, flushing fluid and greasing slide pins on floating calipers is usually enough. Street performance car.... if it's actually driven hard (stopping hard) regularly and running a really aggressive street pad MAYBE rebuild every 100k miles, really depends on the car though, usually just flushing fluid on fixed calipers is enough,