so I did a brake bleed yesterday due to a mushy pedal. right after the bleed, the pedal was good and firm, but within about 2-3 minutes after getting moving, it was back to mush. what gives? vac leak? booster? thanks...

 

It takes several tries to get the brakes fully bled if doing it manually. One key to it is activating the ABS to move any air out of that. One way to do that is to shift into low range and activate your downhill decent feature. Then of course, bleed again and repeat a few times.

If your mushy pedal appeared out of nowhere, you may have a leak in the system.

 

If you have drained through the ABS you need to activate the ABS to bleed the system correctly, many will disagree but read the RAVE workshop manual carefully and you will note this. The only true way to activate the ABS on both A and B circuits is via the OBD2 port with the correct equipment. There is various equipment on the market which can do this but beware it's not cheap.

This is one system on a Defender which is identical to a D2.


Why they bleed diagonally opposite corners of the truck is if you look at RAVE the A Circuit is front left wheel and rear right wheel and the B Circuit is front right wheel and rear left wheel. (wheel refers to the caliper bleeding) Always bleed the brakes according to the RAVE manual, they know best eh and better than rear ending someone