Brake caliper rebuild…. Caliper grease or brake fluid?

[A930Rocket]

I’m rebuilding a set a brake calipers and looking online, folks say to use brake caliper grease on the seal to help the piston slide. In the past I’ve always used brake fluid.

What’s the best way?

[vash]

right or wrong, i used a silcon grease made for lubing o-rings. just the tiniest amount. i never felt comfortable having brake juice on my hands (gloved). i would lean against my wife's car for sure.

[island911]

Using brake fluid is he safest bet.

[hcoles]

When I rebuilt my calipers I went to some effort to get the Plastilube as listed on the rebuild parts package. That stuff was stiff but I used it anyway. The calipers were sticking but that may have been caused by 40 year old brake hoses. That issue went away when I changed the hoses. Most often I hear of people using brake fluid. That's probably the best bet considering it is usually immediately available.

[javadog]

I use a special grease made by Ate.

[Bill Verburg]

Originally Posted by A930Rocket

I’m rebuilding a set a brake calipers and looking online, folks say to use brake caliper grease on the seal to help the piston slide. In the past I’ve always used brake fluid.

What’s the best way?

Use quality brake paste like Unisilikon TK 44 N2

Porsche part # # 000 043 117 00

[A930Rocket]

Well, since I want to rebuild and install them today, I’m limited on my choices. I have brake fluid, caliper grease and silicone paste.

Maybe a little of each!😂

[Superman]

Dow Corning 111 or 112. I use it on all rubber automotive parts. Perfectly safe for DOT 3 brake fluid, which is also what I use in my SC. It is available with a whopping 550+ dry boiling point.

Do not use DOT 5 brake fluid unless your car came with it, in which case you cannot use anything else. Ever. Read up if you are ever tempted, and that will cure you.

[Shaun @ Tru6]

I've restored several sets of Turbo calipers first with Sil-Glyde and then switched over to Unisilikon. No failures with either, and I would certainly know.

[Baz]

Originally Posted by A930Rocket

Well, since I want to rebuild and install them today, I’m limited on my choices. I have brake fluid, caliper grease and silicone paste.

Maybe a little of each!😂

Late to the thread but if those are all you have to pick from I'd go with the brake fluid.

There are a bunch of special lubricant products on the market but nothing wrong with just using brake fluid, if needed.

Good luck!

[Baz]

More on these threads:

https://forums.pelicanparts.com/porsche-911-technical-forum/711546-while-my-calipers-out-their-grease-pistons.html

https://forums.pelicanparts.com/porsche-911-technical-forum/335758-caliper-rebuild-grease.html

https://forums.pelicanparts.com/porsche-911-technical-forum/372778-caliper-rebuild-lube-type.html

https://forums.pelicanparts.com/porsche-911-technical-forum/508935-using-anti-seize-synthetic-grease-brake-caliper-bore-prevent-rust.html

[manbridge 74]

Nothing wrong with brake fluid. But if the attempt is made replacing seals on late GT2 or GT3 calipers you will find extremely close tolerances between the bore and piston. The grease helps immensely….

[SCadaddle]

I recently cleaned and put new seal kits in the brakes on my SC. Read the DIY tutorial and watched the videos from the PMB website since that's what those guys do. Appears they are using a Permatex Ceramic Extreme grease on the pistons and seals. It's purple in appearance. I looked over the Permatex website and their TDS info and it appears their Silicone Ceramic Extreme grease is a newer product supposedly safe for all rubber components. It's orange in appearance. That's what I went with at the local FLAPS. Part no. 24129 about $5. Had plenty to do all the calipers with plenty left over even with a little 0.5 oz. tube.

My inner bores and pistons looked fine once getting them out. I had 3 calipers that were seizing up hence the reason to do the job. The pads upon inspection were on the last mm's of their life. It was very evident that the corrosion in the bores outboard of the seal in the caliper and under the dust boot was the culprit of my hanging brakes, along with the old flexible brake lines I also replaced. That being said, I used the grease in the bores and under the dust boots. I don't think just using brake fluid will do much outboard of the seal and under the dust boots....but initiate and enhance another round of corrosion. My brakes are wonderful now, and I've actually got a car that rolls even on the slightest incline.

[A930Rocket]

Well, I opened up the ATE rebuild kit and it had brake caliper grease, so ended up going with that. I should’ve opened up the box before I posted!

What I had a hard time with, was installing the outer dust seals. It took multiple attempts and different ways to get them installed.

[OK-944]

You might also try brake assembly lube in the bores themselves...especially if they need any amount of honing - to help them settle into proper operation smoothly. Worked wonders in my case.

[cstreit]

PBR rubber grease or Brembo caliper seal grease is what we recommend….

..but I’ve also used brake fluid.