Grease + Brake fluid = :-) ?

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279
Location
Kah-nah-dah
I have my proportioning valve apart at the moment, and I can see some rather nasty signs of wear occuring. Seems at the factory they put lithium grease in a few places but it wasn't looking to keen, sorta yellowed and pasty. The wear is specially noticable on the piston assemblies. So being of the idea that when it looks like it's wearing from moving and contacting the metal around it. But I'm not sure what greases get along with brake fluid or if I should just trust, caliper grease up in here. That's where I get a little leary beacuse the proportioning valve never gets hot and caliper grease tends to seperate. So I then looked at my Amsoil waterproof stuff, and my low temp ep grease, but I don't want the grease to turn abrasive either. So... What do I do?
 
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19,479
Location
Chicago Area
A little specialized grease may be used for storage or assembly, but it is not needed on this part for function. I never heard of adding internal grease to a brake system.
 
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Messages
8,711
Location
Nothern USA
I have actually never had a proportioning valve apart. Any other part of a brake system, I use Sil-Glyde, caliper seals, caliper bolts, wheel cylinders, etc. I don't know how good its anti wear properties are, but it gets along fine with brake fluid and the rubber parts.
 

gamefoo21

Thread starter
Messages
279
Location
Kah-nah-dah
Thanks, yeah I know the proportioning valve is supposed to be a sealed unit, but metal top cap, was getting cancerous rust, and the rest of it is shiny aluminum. It came apart so easily it's almost as if it was meant to be serviced.
 
Messages
37
Location
Tacoma WA
NEVER use a petoleum based lube or oil inside a brake hydraulic system. You will swell the rubber seals and cause a failure. There are assembly lubes used at time of manufacture that are compatable with the hydraulic system.
 

gamefoo21

Thread starter
Messages
279
Location
Kah-nah-dah
Alrighty, I went out and picked up a small tube of lube that is ceramic based that says it lubes everything. Even shows a diagram saying to put it on the outside of the caliper piston, behind the rubber seal, since it protects the rubber and provides lubrication. Oh and I can't buy a new one, they are very muchly unavailable from the dealer. So that's why this one is being treated with such care.
 
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22,708
Location
CA
 Originally Posted By: gamefoo21
Alrighty, I went out and picked up a small tube of lube that is ceramic based that says it lubes everything. Even shows a diagram saying to put it on the outside of the caliper piston, behind the rubber seal, since it protects the rubber and provides lubrication. Oh and I can't buy a new one, they are very muchly unavailable from the dealer. So that's why this one is being treated with such care.
Is it the Permatex Ceramic Extreme Brake Parts Lubricant? The purple stuff?
 

gamefoo21

Thread starter
Messages
279
Location
Kah-nah-dah
 Originally Posted By: The Critic
Is it the Permatex Ceramic Extreme Brake Parts Lubricant? The purple stuff?
I ran outside to grab it(long day at work + flu = what's my name?) and yep. On the back of the package is a diagram showing the "general" break down of all the parts of your typical caliper and has arrows to every part saying it can go here.
 
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