My 90 fox has a leak at the right rear brake, and I'm adding fluid as needed, but I don't know - will the leak get worse, and can that happen suddenly? The brakes are spongier than they have been. also, I'm adding Valvoline SynPower to a system that already has some SL (German) fluid in it, as well as some of the old fluid that I never got a chance to flush out.
The Valvoline says it's DOT 3 and 4 compatible, and suitable for ABS systems, so it sounds like it's better than the cheap brand.
Is the Valvoline really any better, and will my leak suddenly get worse?
TIA Tom Seattle