Has anyone done a brake system flush? Last one I did was on a military trailer about nine years ago. If I'm not mistaken, the way it was done was by using denatured alcohol pushed through the brake system. Is this correct?
Boy, I was taught never to put anything but brake fluid in the system. Ever. All you're trying to accomplish is get the old fluid out that's absorbed water (corrosion risk) and lost other properties at the calipers from high heat cycles. The new fluid simply begins anew doing the job of transferring force through the brake lines.
I'd be worried about any attempt to clean with something that may damage/dry out the system seals. Huge $$$ to replace.
x2 on just using clean fluid to flush out the old. If its just to get rid of the old fluid there is no reason for any cleaning agent. For cleaning brake parts during repair work I just use Brake Cleaner or Metho.
i think there is no need to flush the brake system with fluids other than for the brake. same goes for engine, transmission, powersteering. flush with the fluid you use for the system. there is no combustion or sludge build up that occurs in the brake system to worry about.
The reason I mentioned the denatured alcohol for flushing was that when I was in the US Air Force, we flushed the brake systemf of th trailers used to move nukes. The alcohol waht it does is remove al contamints, including water and the alcohol once is exposed to air it evaporates. We never had issues with damaged seals, as a matter of fact it was required to be done. We also used DOT 5 silicone based brake fluid, never seen it in the civilian market. I used it on my 40 when I was active duty, but when I retired and moved, I had no longer access to it.
Here is some information about DOT 5. Based on this information, not sure I would want to run it in my truck. Seems like to Cons outweigh the Pros.
Silicone Brake Fluids
In years past, all brake fluids were glycol. Then D.O.T. 5, a silicone fluid having a higher temperature rating, emerged, initially to meet the higher boiling point requirements of racing use. (Race car brake systems include oil-cooler-like heat exchangers and ceramic pads.) Silicone fluid was able to withstand the most heat of any brake fluid, so it earned a reputation as a racing brake fluid. However, silicone brake fluid has properties very different from glycol fluid, and has its own pros and cons. On the advantage side, silicone fluid will not harm paint or plastic, and does not aggressively attract additional moisture as glycol fluid does. On the disadvantage side however, silicone fluid aerates easily. Harley-Davison, one of the sole current OEM users of silicone fluid, warns buyers to let the fluid sit at least an hour before using it. The trip home in the saddlebag is enough to aerate silicone brake fluid until it looks like a freshly poured soft drink. Silicone fluid is also slightly more compressible than glycol fluid, does not change color to tip the user to its moisture content, and worst of all, neither accepts or disperses moisture, making systems using it more corrosion prone, and requiring much more frequent fluid changes. Silicone brake fluid also lacks glycol fluid's naturally occuring lubricity, making it incompatible with the mechanical valving in some antilock braking systems.
Probably the main reason USAF used silicone brake fluid was heat dispersion. I'm not going to use it, I'm going DOT 4 synthetic. However I'm flushing the brake system very soon.
