How to clean brake system for DOT 5 switch

[ZacharyB]

My calipers are sticky and I don't want it to happen again. How would I purge every last instance of DOT 4 from my brake system and introduce DOT 5? Flushing the lines with water sounds too easy and incorrect.

I also understand DOT 5 will turn to a gelatinous goo if the system is too old, and become worse than DOT 4! (Used the search feature!) I have no way of inspecting the inside of my lines and I am on a budget. If it is too risky, I'll just stay with what I know...

[KennyJ]

DOT 5...silicon. Have used it in my race car and never plan on using it again. Terrible stuff, if it airates (poor spelling) it can take hours for the bubble to disappear, has problems with elevation changes, and all in all is just too dang expensive. Just run some good DOT 3 or 4 and change it every 2 or 3 years.

Just my experience, use rubbing alcohol or brake cleaner (alcoho based) to clean and flush the line.

Kenny

[ZacharyB]

DOT 5...silicon. Have used it in my race car and never plan on using it again. Terrible stuff, if it airates (poor spelling) it can take hours for the bubble to disappear, has problems with elevation changes, and all in all is just too dang expensive. Just run some good DOT 3 or 4 and change it every 2 or 3 years.

Just my experience, use rubbing alcohol or brake cleaner (alcoho based) to clean and flush the line.

Kenny

OK, I'll keep using DOT 4... sounds easier to pull apart the pistons to clean 'em every so often than to deal with braking problems

[Wingnut]

Silicone Grease

When I rebuilt my calipers I found the corrosion to have come from the external side of the piston O-ring. The little rubber boot just doesn't do a good job of keeping all of the moisture out of the piston bore. So upon reassembly, once the piston is pressed back in I pack the outer edge of the piston, between the piston and the dust boot, with silicone grease. I always do this on cars and bikes and have had good luck so far. The silicone doesn't contaminate the brake fluid because it's on the other side of the o-ring. Eliminates repedative disassembly.

bob

[ZacharyB]

I just remembered "DOT5=Silicone, DOT4=? Oh yeah, glycol, alcohol." Since antifreeze is glycol too, could it be used in a pinch as something like DOT2 or 1?

What makes brake fluid so corrosive to paint if antifreeze won't do the same thing?