1998 e350 rear drum brakes not engaging!!

ocwrestler160 · 09-16-2009, 04:03 PM

i have a 98 e350 work van. when ever i get my brakes check the front rotors are warped and need to be replaced but the rears are brand new practicly. I believe this is because the rears only engage for the first 10-20 miles after being adjusted. i really could use the extra stopping power for this fully loaded down lug but auto shops and ford themselves have no answers. has anybody heard of this or had this happen to them on the same rig and know of any fixes if so let me know asap please. Thanks much,
Jared-

BroncoJoe19 · 09-16-2009, 08:21 PM

Drum brakes are not all that complicated.
The wheel cylinders may be seized
The self adjuster wheel may be siezed, or
the return spring on the self adjuster may be 10 years old and tired.

BTW I think that 20 miles is a little exageration.
IF you are serious.... that it is only 20 miles or so, then the hydrolics are shot.
If it is more like 1,000 miles or so then it might more likely be the adjusters.

ocwrestler160 · 09-17-2009, 03:37 PM

i have had the whole rear braking system replaced by a ford dealer and still the same end result and yeah the mileage is probly not correct but either way its no good i could really use that extra stopping pressure, too many close calls if you know what i mean. But realisticly im curious to see if anyone else has had the same or similar problem or heard of anyone having this problem as well. thanks again
Jared-

BroncoJoe19 · 09-17-2009, 05:59 PM

I don't know if and when they changed the system, but as I recall, and it is only from what I read. With trucks that had RABS rear antilock braking systems, I think that there is a control valve that will bleed the brake fluid back to the master cylinder when the ABS is activated, and it sometimes gets stuck open thereby always reducing the pressure to the rear brakes.

theoldwizard · 09-18-2009, 12:20 AM

Joe is on the right track about the proportioning valve, but this probably has nothing to do with ABS/RABS.

Before ABS/RABS came along, pickup truck and vans were set up to have a very heavy front brake bias. This is because when they are empty the rears brakes are useless. (My E150 rear brakes look like new after 90k+ miles, but I drive it empty 99.9% of the time.)

You need to find a real brake expert and see if he knows a way to change the front/rear brake bias. (Race car catalogs sell adjustable brake bias proportioning valves.)