Quote:
Originally Posted by DEMON Dot 4 is glycol based fluid, absorbs water. dot 5.1 is silicon based and does not absorb water...so any water / moisture found in the dot 4 system is usually absorbed into the fluid. With dot 5.1 it does not absorb water, therefore any in the system accumulates at the lowest point, ie your calipers and causes corrosion there!! |
Thanks, demon. Perhaps I shouldn't run DOT 5.1 after all.
The reason I do so is because I assumed the DOT 5.1 fluid would eliminate the problems associated with water since it doesn't absorb moisture but I guess I misunderstood the whole concept.
I replace the brake/clutch fluid at least twice every season but I guess water could remain at the bottom of the calipers since the bleeder nipples are positioned at the top of the caliper instead of the bottom. Even if you connect a vacuum hose to the bleeder nipple you probably won't succeed in emptying the calipers completely.
Is there some indication of water still being trapped in the system? How about discolouration of the fluid? Will that still occur with no water whatsoever in the system?
Why does the fluid darken over time anyway?
And other than DOT 4 being hydroscopic what else is different when comparing DOT 4 and DOT 5.1? Is DOT 4 capable of handling the same amount of heat as DOT 5.1?
Thanks! And sorry for this partial threadjack.