Rear Brake Caliper Upgrade?

[Alistair Francis]

I bought my 1996 1.9L Z3 a year and a half ago (used obviously) and at the time had the front brakes replaced. I can't remember if the mechanic replaced the calipers, but the pads and rotors were replaced.

I recently went to a track event and now the brakes squeak just before I come to a stop. I think the sound is coming from the back brakes, but it is hard to tell. I decided I will replace the rear pads and rotors and see if that fixes the noise. It's something I need to do at some point anyway.

I was looking at these pads: [1] and these rotors: [2]. Any thoughts on their quality and interoperability?

What I can't tell is if it is also worth replacing the calipers. It looks like if I don't change the calipers I can get away without bleeding the brakes, which I really don't want to do.

The car has spent a fair bit of time around saltwater so the wheel drums are all pretty rusted, which makes me think the calipers aren't in a great state. The car has 150,000miles on it and I'm not sure if/when they were last changed. I don't notice any leaking brake fluid though.

Does anyone have any advice on if they should be changed?
Also, if I'm going to the effort of changing them are there performance calipers worth getting? I was looking at either: [3] or [4]

[1]: https://www.tirerack.com/brakes/brakes.jsp?make=Hawk&model=High+Performance+Street/Race+Pads
[2]: https://www.tirerack.com/brakes/bra...roup=Sport+Slotted+Rotor&partNum=126.34040PSL
[3]: https://www.turnermotorsport.com/BMW-Z3/c-82-bmw-brake-calipers
[4]: https://www.carid.com/1996-bmw-z3-b...-semi-loaded-disc-brake-caliper-52484824.html

I attached a picture of the back caliper, I'm shining a torch on it which is why it is so bright.

 

[Alistair Francis]

Digging into it a bit more it sounds like I might replace them. There is a discussion here [5] where some people think they should be replaced and some think they shouldn't as there doesn't appear to be anything wrong with them. Either way thought it sounds like the brake fluid should be bled, and if I'm doing that I'll just replace the calipers.

[5]: https://mechanics.stackexchange.com...hat-point-do-you-need-to-replace-the-calipers

 

[hard top]

@t-tony could help you with that, he's state side now ....

 

[the Nefyn cat]

Back in my motorcycling days it was said that if you can still use the back brake you're not using the front ones hard enough. Having said which, you need to get the back end up in the air and find out if the brakes are applying properly when you press the pedal and releasing when you let the pedal off again. If they're working OK then no need to change them. Don't know about over there, but here it's a whole lot cheaper to buy a set of seals and refurb the calipers you've already got, at least that way you can be sure you've got the right ones.
New discs may help more than new calipers, but it's hard to tell from here. And these rear brakes are a bit prone to have noises inside from the handbrake bits.

 

[Alistair Francis]

Thanks for your advice. I decided I won't change the calipers then.

I'm just going to measure the thicknesses of the pads and rotors and go from there. Hopefully I can avoid changing anything for now