Topic: Brake assembly lube for caliper piston seal

[manjisann]

I have read many of the threads on this and know what I'm looking for I just can't find it on the net.

I know Lloyd recommends the Raybestos Assembly fluid and even provided a link to a place that carries it. The problem is they don't ship and there are none of their stores in Utah. Does anyone know where I can find this fluid in Utah? I want to do this right and not install the seal dry or lube it with the brake fluid, just not haveing any luck finding any of the stuff.

Any suggestions?

Brandon

[Toxic]

i don't know where you can get that specific brand but this one by Permatex is designed for this application.

[manjisann]

Thanks, I remember  you posting this in the thread I read. I went back and reread it and realized I misunderstood what TT was saying about it. If I read it correctly now, this stuff is fine for lubing the caliper seal, he was just saying there was some doubt as to whether or not it would work for between the piston and puck as he hadn't tested it. Thank you for helping to point this out. I think the local autoshops have something similar to this and I'll pick some up.

Brandon

[Duke McDukiedook]

McKay brand is one to try and get if you can't get the Raybestos.

[TwoTired]

More confusion, it would seem...

The stuff posted by Toxic, may well work behind the brake puck, if it won't creep, run, or melt into the friction pad.
I am skeptical it is properly used on the caliper seal itself though, as some of it will get inside the DOT3 containment vessel.  I just can't find enough data on it to tell if it will cause some adverse reaction in that event.
What I can find is here (courtesy of Gordon):
http://www.permatex.com/products/Automotive/specialized_maintenance_repair/maintenance_repair/Permatex_Countermans_Choice_Ultra_Disc_Brake_Lube.htm
The MSDS says it is insoluble in water (good for behind the brake puck as it should shed water and prevent corrosion.
It is >90% synthetic based oils and trade secret composition., Green semi solid (over what temperature range?)
Suggested Applications: Caliper pins, sleeves, bushings and pistons.

There is no mention of caliper seals.
No mention of areas immediately adjacent to friction pads either.
I'd test it before committing to SOHC4 caliper use.  Unless, you don't mind having the friction pad lubricated unintentionally as an experiment.  I've done this experiment with another product and lived.  But, I wasn't happy about it!

Cheers,

[manjisann]

I'll also look for the Mckay brand. When I was looking around I found several small squeezy packets that said they were for rubber parts in the brake system, so I wonder if they will work for the seal. I have the Dow Corning grease for behind the puck, just gotta find this stuff.

To test if it will work properly, do I just take some Dot 3 brake fluid and drop a bit of the lube in and see if it will mix with it, as apposed to staying a blob, or worse solidifying?

Thanks,

Brandon

[manjisann]

http://www.permatex.com/documents/tds/Automotive/24110.pdf

How about this, it says it's good for internal rubber?? Does that mean rubber that comes into contact with the brake fluid? Sorry, some of the wording is a bit vague to me.

Brandon

[Toxic]

More confusion, it would seem...

The stuff posted by Toxic, may well work behind the brake puck, if it won't creep, run, or melt into the friction pad.
I am skeptical it is properly used on the caliper seal itself though, as some of it will get inside the DOT3 containment vessel.  I just can't find enough data on it to tell if it will cause some adverse reaction in that event.
What I can find is here (courtesy of Gordon):
http://www.permatex.com/products/Automotive/specialized_maintenance_repair/maintenance_repair/Permatex_Countermans_Choice_Ultra_Disc_Brake_Lube.htm
The MSDS says it is insoluble in water (good for behind the brake puck as it should shed water and prevent corrosion.
It is >90% synthetic based oils and trade secret composition., Green semi solid (over what temperature range?)
Suggested Applications: Caliper pins, sleeves, bushings and pistons.

There is no mention of caliper seals.
No mention of areas immediately adjacent to friction pads either.
I'd test it before committing to SOHC4 caliper use.  Unless, you don't mind having the friction pad lubricated unintentionally as an experiment.  I've done this experiment with another product and lived.  But, I wasn't happy about it!

Cheers,

TT the packaging clearly states it is for use on the seals.  FYI
I think the bottome line is you need to find a product that is available in your area and make sure it is designed for your intended use.

[manjisann]

I think the bottome line is you need to find a product that is available in your area and make sure it is designed for your intended use

That is what I am trying to do. Toxic, do you know if that stuff will disolve in the DOT 3 brake fluid? If I am understanding everything right, that is one of the things it needs to be able to do, be compatible with the fluid so it won't turn into a solid lump and plug up the works.

Brandon

[Toxic]

It is designed specifically for use on the back of the brake pads and to lubricate the brake caliper seals.

From the back of the package:
100% synthetic
40 to 400F
stops brake squeal and chatter
waterproof, protects against corrosion
lubricates entire brake assembly
safe on rubber and plastic parts

Directions:
Lubricate Brake Parts
1/ clean all brake parts
2/ apply to caliper pins, slides, clips, bushings, pistons, rubber sleeves and seals.
Stop Brake Squeal
1/ clean the back side of brake pads
2/spread a thin even coat to the BACK of the inboard and outboard pads.
DO NOT APPLY TO THE ROTORS OR THE BRAKE PAD SIDE FACING THE ROTOR.

I hope this helps.

[mick7504]

Silicon based lubricant is fine on brake fluid compatible seals and is beneficial for their operation.
Generally there is no need to put any compound between the disc pad (puck) and the caliper piston unless there are problems with brake squeal.
In the case of brake squeal there are products available which help to eliminate this problem but are solely designed for that application.
It is a "rubbery" type of compound similar to the every day silicon sealant and helps to absorb vibration generated between the disc pads and the disc rotor under application that is the source of brake squeal.
Caliper slide pins can be lubricated with a special synthetic grease designed for that purpose.
Applying petroleum based lubricants to brake fluid compatible seals will end in disaster.

[Duke McDukiedook]

Silicon based lubricant is fine on brake fluid compatible seals and is beneficial for their operation.
Generally there is no need to put any compound between the disc pad (puck) and the caliper piston unless there are problems with brake squeal.
In the case of brake squeal there are products available which help to eliminate this problem but are solely designed for that application.
It is a "rubbery" type of compound similar to the every day silicon sealant and helps to absorb vibration generated between the disc pads and the disc rotor under application that is the source of brake squeal.
Caliper slide pins can be lubricated with a special synthetic grease designed for that purpose.
Applying petroleum based lubricants to brake fluid compatible seals will end in disaster.

You might want to brush up your reading on this, start in the FAQ area on brakes.

[TwoTired]

Generally there is no need to put any compound between the disc pad (puck) and the caliper piston unless there are problems with brake squeal.

I can't agree with this and neither did Honda (the shop manual specifies silicone grease to back of pad, piston, and caliper areas exposed to water ingress).
Water and impurities behind the puck will cause galvanic corrosion, as it acts like electrolyte between the steel components and the caliper aluminum, causing the materials to corrode.  The silicone grease coating stop water contact with these metals.

Applying petroleum based lubricants to brake fluid compatible seals will end in disaster.

Totally agree with this. Petroleum products often cause rubber to swell.  That's why a synthetic lube is recommended for the caliper seal proper, and brake parts assembly lube is the known material used for this application.

Cheers,

[manjisann]

So if petroleum based products are bad, what base am I looking for??

From what I understand silicone in at least DOT 3-4 fluid is a bad idea as it will form a blobish sludge which I imagine will eventually plug up several of the orifices that are critical in the MC. Plus if silicone grease was ok, then the Dow Corning grease would work for both sides of the application.

Sorry guys, I wasn't trying to start another thread on what to use, more of a where do I find it in the desert? At this point I'm toying with the idea of filling it with bread pudding mix, going for a ride and after hitting the brakes really hard and crashing, opening it up and enjoying a final meal 

I tried one of the local brake parts suppliers that several separate stores referred me to (without me mentioning them) but the one guy I talked to had no clue what I was asking about, so he transferred me to the guy who would know, and I left a voice mail, with my info and what I was looking for. I have yet to hear back from them and with all the luck I've had tracking this stuff down I'm really not holding my breath that i'll get a call back.

Seriously at this point I think I'm going to check out some of the little packets of stuff the chain stores have and see if any of them are DOT 3 soluable, and thus I assume ok to use.

It's a shame I'm not replacing my brake hose right now or I could just jump to DOT 5 as everything else has been boiled out. Oh well, Se La Vi (or however that is spelled.)

Brandon

[Duke McDukiedook]

Try here, this is where I got it from.

http://aaabrake.net/CHEMICALS.aspx

This is the company that makes it. You might want to call the number to see if anyone distributes it near you.

http://www.airosol.com/50600.html

If worse comes to worse, for some reason I bought 4 bottles of this stuff (one bottle will last forever), I could sell you one for my cost and shipping.

[TwoTired]

So if petroleum based products are bad, what base am I looking for??

Brake assembly lube is a synthetic base (MSDS says Polyether Polyol), that won't react adversely with DOT3 brake fluid.  It also keeps the seal to caliper interface protected against water, either absorbed by the brake fluid or entering behind the brake puck.

I'm sorry it's not more readily available in your area.

However, if you need a drink of water, drinking anything that looks like water may not be in your best interest.

When you reach your limit of search ability, then use brake fluid to lube the caliper seal.  Just expect to rebuild your caliper again at a more frequent interval than if you had found the brake parts assembly lube.  (5 years instead of 10? ... a guess  )

[manjisann]

When you reach your limit of search ability, then use brake fluid to lube the caliper seal.  Just expect to rebuild your caliper again at a more frequent interval than if you had found the brake parts assembly lube.

I choose option C, beg Dukiedook for one of his bottles of unobtanium!

Oh Saint Dukidook, patron saint of motorcyclists 

Just called aaabrake.com and they said they are on backorder for 3 months.

If I have to look for an alternative this

So if petroleum based products are bad, what base am I looking for??

Brake assembly lube is a synthetic base (MSDS says Polyether Polyol), that won't react adversely with DOT3 brake fluid.  It also keeps the seal to caliper interface protected against water, either absorbed by the brake fluid or entering behind the brake puck.

will help imensly in know what may or may not work. See I'm asking these questions because I want to use the correct stuff, but when it is unobtainable, I want to know how to find alternatives.

Thanks,

Brandon

[manjisann]

Ok, so for anyone else that stumbles upon this thread in their frustrating search for the proper stuff to lube the piston seal, here is what I have found/learned.

First, this crap is at least 75% unobtanium, at least here in the wild west.

Second, http://www.airosol.com/50600.html these guys are actually selling the stuff (McKay Brake Caliper Assembly Lube.) At the time that I am writing this, they don't have the cart function set up on their website, but if you call during business hours they will gladly process an order for you over the phone (at least that is what the polite gentleman told me when I called, I didn't ask if there was a minimum order, but hopefully there isn't.)

Third, I've found that many sources, not just the FAQ and TT, but other independant sources mention that mixing DOT 3 & 4 with any silicone based lube is a recipe for disaster. The two are not compatible with eachother and the silicone will turn into a lovely crud collecting sludge. IMO this is bad with all the little orifices that are in our brake systems.

Four, as always, this forum has the cream of the crop when it comes to members willing to help eachother out!

Brandon

[mick7504]

Generally there is no need to put any compound between the disc pad (puck) and the caliper piston unless there are problems with brake squeal.

I can't agree with this and neither did Honda (the shop manual specifies silicone grease to back of pad, piston, and caliper areas exposed to water ingress).
Water and impurities behind the puck will cause galvanic corrosion, as it acts like electrolyte between the steel components and the caliper aluminum, causing the materials to corrode.  The silicone grease coating stop water contact with these metals.

Point taken.
On the other side of the coin, lubricant on the expose surface of the caliper piston will attract impurities.
It's all very arguable.
A facility for a rubber dust boot over the piston would have been a better design.

Applying petroleum based lubricants to brake fluid compatible seals will end in disaster.

Totally agree with this. Petroleum products often cause rubber to swell.  That's why a synthetic lube is recommended for the caliper seal proper, and brake parts assembly lube is the known material used for this application.

Cheers,

[mick7504]

Castrol Red Rubber Grease has been used in the brake industry here in Australia for many many years for the assembly of hydraulic brake components. Castrol GRR(B)
In more recent years, a clear liquid (Hydraulic Brake Assembly Fluid) has hit the market and is excellent for assembling disc brake calipers with aluminium housings and is also compatible with Dot 3 & 4 fluids.
When Dot 5 (Silicone Brake Fluid) became available, it also became a "must have" for some people who ultimately paid the price for a complete rebuild of their hydraulic systems as it destroyed the rubbers that had previously been running in the earlier types of brake fluid. This was especially so in older vehicles.
The best thing that you can do is to flush some clean brake fluid through the system once a year as it does absorb moisture over time.
A brake specialist should be able to point you in right direction.
As far as putting any type of compound behind the disc pad/over the exposed surface of the piston, I think that is really an individual choice. There are pros and cons about doing that.
Good luck with it all.

[Ewan 500K1]

Red Rubber Grease Tech Dta Sheet is here:  http://www.bp.com/assets/bp_internet/castrol/castrol_south_africa/STAGING/local_assets/downloads/t/Red_Rubber_Grease_TDS.pdf
its compatible with brake fluids

[billingstitan]

I've also searched high and low for an alternative to McKay's (well, first for McKay's, then an alternative)

This was recommended in another forum - but wanted to run it by the Masters here at SOHC4.net 

Is it an acceptable substitute? http://www.wilwood.com/BrakeFluid/BrakeFluid.aspx


Wilwood’s specially formulated Synthetic Assembly Lubricant is designed to be used on pistons and rubber components when overhauling brake calipers, wheel cylinders and master cylinders for maximum protection and performance.

Comes in a convienient 4oz bottle size, with applicator tip. Also available in a case of 12 - 4oz bottles.

[Duke McDukiedook]

You can't download the product data sheet but if it is assembly lube it should be safe with Dot 3 and 4. Not sure if it is OK to use with 5.1.

[TwoTired]

Sure looks like the right stuff for the caliper seal only, not for use behind the brake puck, as it will run/bleed into the friction pad and rotor.

I bought a bottle of assembly lube from Raybestos, too.

Cheers,

[Lostboy Steve]

I used the green brake caliper grease. The one that comes with the brush attached to the cap. You can buy it anywhere.

[Duke McDukiedook]

I used the green brake caliper grease. The one that comes with the brush attached to the cap. You can buy it anywhere.

Alright, I'll bite.

To do what exactly?