So I just swapped a dana 60 into the rear of my jeep. Everything is hooked up, not leaks or anything. I bled the brakes 3 times. When the vehicle is not running there is normal pressure, once the vehicle is started there is little to no pressure. I pulled the vacuum line off of the booster while it was running and the brakes go back to normal.
What could this be? I don't see it being bad seals on the master cylinder because it only sat not running for a couple of weeks and always had fluid in it. I adjusted the brakes on the rear of the new axle and you can hear them rub all the way around when you spin the tire so there isnt excess space in there.
Please help, this is urgent, I start school on thursday and need to get it driving.
P.S. - Can't test drive it to see if it stops due to the stock rear drive shaft being too long and too thin to use with a dana 60, towing it to drivelines soon to have a new one made.
Last edited by MoreBassXD; 09-01-2014 at 10:07 PM..
Reason: added info
you got rear drums? I'd check to make sure the star wheels are properly adjusted.
If you can't get that initial squeeze on the brakes for centering the shoes, it can feel like they are properly adjusted (slight dragging) even if they are not.
Oh, I do seem to have forgotten to spin the wheel and slam on the brakes XD maybe that could be part of the problem, but I still don't see why it would have pressure when it was not running but doesn't when it is running.