Hi all,
A while ago, my stock MC started to fail on my HZJ77, I had an MC from an 80 series handy so I used it to replace the stock one. Bolt pattern matched, both vehicles have front and rear disc brakes so I figured it should work the same. Been running this for a while and the brakes work fine, but I did start noticing some sponginess once fully depressed. Best way I can describe is it gets firm upon initial depression, but then there is a slow give where the pedal continues to travel. When this happens the brake light on the dash illuminates intermittently. I thought that light only comes on with the ebrake and if the fluid in the MC gets too low? Definitely neither is happening when it flickers on/off. There is a wire that comes off the vacuum reservoir, is that light monitoring vacuum as well?
I've bled the system until blue in the face, lines are all new, calipers are new.
So my question is could it be the mismatched MC? Are Boosters and MC designed specific to work with one another? Or is it vacuum related?
Thanks all,
A while ago, my stock MC started to fail on my HZJ77, I had an MC from an 80 series handy so I used it to replace the stock one. Bolt pattern matched, both vehicles have front and rear disc brakes so I figured it should work the same. Been running this for a while and the brakes work fine, but I did start noticing some sponginess once fully depressed. Best way I can describe is it gets firm upon initial depression, but then there is a slow give where the pedal continues to travel. When this happens the brake light on the dash illuminates intermittently. I thought that light only comes on with the ebrake and if the fluid in the MC gets too low? Definitely neither is happening when it flickers on/off. There is a wire that comes off the vacuum reservoir, is that light monitoring vacuum as well?
I've bled the system until blue in the face, lines are all new, calipers are new.
So my question is could it be the mismatched MC? Are Boosters and MC designed specific to work with one another? Or is it vacuum related?
Thanks all,
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