Brake caliper grease

[teK--]

What do you guys use when re-greasing your caliper slide pins (non-Brembos)?

I have used the green Permatex Ultra Brake disc lube on a few occasions before, but it causes the little rubber bush (pic as below, bottom of pin on left) to swell up within hours, causing the pin to drag/seize up and the caliper to start binding.





Even though the Permatex and quite a few other products are listed as safe for rubber seals, various forums (Honda, Toyota, Subaru, Dodge etc) report that this causes this swelling issue.

The best stuff I have come across is the Niglube RM grease (comes in a satchel with the Subaru caliper seal rebuild kit), but it is not available separately locally. They pack this stuff in from factory and the calipers still work great 6 years later.

I need something this weekend. Any ideas?

[rickerty]

What about O-ring grease? Some are good up to 800ºC and will not effect the properties of the rubber.
Even if you were to only use it on the seal end to limit the swelling?

[teK--]

I'm not sure about this description, it isn't confidence inspiring :

Dow Corning® 55 O-Ring Lubricant is a soft silicone-based grease, slightly swells rubber for better sealing, oxidation resistant and serviceable over a wide temperature range.

Got any other suggestions Rick? You must have a good selection in your workshop .

I'm so tempted to pilfer some of the old grease out of some stock calipers I have sitting in the shed. The slide pins in those are smoother than the ones I just packed full of grease today!

[rickerty]

No doubt we'd have something at work but we're closed 'til Wed.
Must be different o-ring grease types, I use one at work that doesn't affect the rubber - no swelling / no shrinking. Then again the boys in o'haul require the type that expands the seal
I do have a tube in the garage that I brought home a few weeks ago, i'll have a look in the morning.

[teK--]

I have found a very similar substitute which Toyota uses from factory and is sold separately (overseas). Part #08887-01206 "Rubber Grease".

All the Toyota guys who had rubber swelling from the regular brake greases have gone back to this OEM grease and it fixed the problem.

I'm going to call Toyota on Wednesday and see if we can get it in Australia.

In the meantime, I boiled the swelled bush in hot water for a few mins to sweat all the solvents out which were causing it to swell. Then I scooped the old grease out of my old calipers and used that on this one sticky pin. So far, so good.