mtndrvr

The front rotors on my 2021 GT4 (9,500 miles on odometer) were scoring rather significantly so I removed the calipers and rotors to inspect all the parts. It has all OEM parts (red six piton calipers, iron cross drilled rotors). I found two obvious problems:

1. The dust seals on several of the caliper pistons are cracked in multiple places and significantly deteriorating.
2. One of the yellow plastic/ceramic caps on one of the pistons is cracked and pieces of it are falling off.

Several questions:

1. Is anyone aware of similar problems with 2020/21 GT4s?
2. Does anyone think one or both of these problems are covered by the Porsche warranty?
3. Does anyone know anyone that has replaced the dust seals or the yellow plastic/ceramic piston caps on these brakes? And that is willing to provide guidance to me to perform the repairs.
4. Does anyone know any repair shop (other than Porsche dealer) that could replace the dust seals and the yellow piston cap?

Thanks for any guidance you can offer.

enduro

These issues are known to exist if the car has been tracked. Caps and seals are replaceable separately from the calipers.

mtndrvr

Thanks. Do you know where I can buy the piston seals and piston caps? One Porsche dealer states Porsche does not sell the piston caps or piston seals (only the dust covers).

Dr.Bill

Known issue in tracked cars.
Thought to be due to heat. Particularly if you run with all the nannies on - they apply brakes and generate heat.

There are one or two vendors who make titanium replacements for the ceramic pucks.
Here is one:
https://rennlist.com/forums/991-turb...-ceramics.html

At least one person has had this covered under warranty. Might depend on your relationship with the dealer and how they view hard use.
See here:
https://rennlist.com/forums/991-gt3-...l-pistons.html

mtndrvr

Thanks again - very informative links.

edub

What nannies specifically need to be turned off? ESC or both ESC and TSC?

swberry

I have re built the calipers on my 981 due to the dust boots and seals deteriorating. This is from tracking the car as previously stated. I purchased the dust boots, seals and pistons from racingbrake.com. They have every inner component of the caliper you would need. They also have high temperature dust boots for the caliper. I think those dust boots were blue in color instead of black like the "standard" temperature boots. The job is not difficult (you just need some time to set aside) and as I recall they provide a pretty detailed instruction pamphlet along with the right type of grease to use. So..... Yes you can buy these individual parts and get this done yourself.

Having said all that... I have a new 718 4.0 soon to be delivered that will be tracked almost exclusively. Based on my experience with this I plan to try out some titanium heat shields that can be purchased from girodisc. I do not know if these will protect the dust boots any better, but I am going to give it a try.