Brake problems
Thread Starter
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Senior User
Joined: Feb 2001
Posts: 120
Likes: 0
From: Wisconsin
Brake problems
I've got an 89 F150 Supercab 4x4..I've put almost all new brakes in the truck. I hardly have any brakes though...I replaced the front pads and calipers, rear shoes, drums and all of the hardware. I swapped out the master cylinder yesterday, and I'm no farther ahead than I was before...the pedal goes almost all the way to the floor....I swapped out the power booster for a used one today, no dice. The only other thing I can think of is the ABS for the rear wheels...I had it jacked up and put the truck in drive...the rear wheels barely stop when I apply the brakes...I've tried to adjust and adjust...I've bled and bled, no good...
When I do step on the brakes hard enough with the wheels in the air, the ABS box makes a hell of a racket....not so on the road when I test it...
Any thought?
Thanks!
Phil
When I do step on the brakes hard enough with the wheels in the air, the ABS box makes a hell of a racket....not so on the road when I test it...
Any thought?
Thanks!
Phil
Post Fiend
Joined: Jun 2002
Posts: 13,873
Likes: 3
From: Atlanta GA
Toecutter,
Did you bench bleed the mstr cyl?
Rebleed the whole system including the RABS.
Then, see if your rear drums are properly adjusted. If the rear drums are not locking up solid when the parking brake pedal is 1/2 way pushed down
(unless you have one of those that push all the way to the floor to release it without a handle)
your rear brakes need to be adjusted.
Ideally, you should adjust the brakes BEFORE you put the drum back on so the drum barely goes back on without forcing it. That way you know the shoes do not have to travel far to engage the drum AND you do not waste a bunch of time under the vehicle adjusting brakes.
They sell drum calipers to help do this. Basically, you measure the inside of the drum, then take the calipers and move out the shoes to contact it. That way the brakes are perfectly adjusted when you put the drum on. It is how they use to do it for the old four wheel drum brakes where the drums are pressed unto the hub.
Did you bench bleed the mstr cyl?
Rebleed the whole system including the RABS.
Then, see if your rear drums are properly adjusted. If the rear drums are not locking up solid when the parking brake pedal is 1/2 way pushed down
(unless you have one of those that push all the way to the floor to release it without a handle)
your rear brakes need to be adjusted.
Ideally, you should adjust the brakes BEFORE you put the drum back on so the drum barely goes back on without forcing it. That way you know the shoes do not have to travel far to engage the drum AND you do not waste a bunch of time under the vehicle adjusting brakes.
They sell drum calipers to help do this. Basically, you measure the inside of the drum, then take the calipers and move out the shoes to contact it. That way the brakes are perfectly adjusted when you put the drum on. It is how they use to do it for the old four wheel drum brakes where the drums are pressed unto the hub.
Thread Starter
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Senior User
Joined: Feb 2001
Posts: 120
Likes: 0
From: Wisconsin
Yep, the MC was bench bled. The rear brakes are adjusted as far as they'll go without binding. I've bled the entire system starting from the RR, then LR, FR, and FL with the RABS bled out before I did the front wheels. From what I can tell, I have no proportioning valve, not sure if it was replaced, what's there now is the line from the cylinder going into a 3 way splitter for the front wheels. You can't pump the brakes up, at least when it is running. When the vacuum is disconnected from the power booster, then I have a good hard pedal, and the truck stops just fine...hook up the booster, and I'm back to the pedal sinking almost to the floor...
Thanks!
Phil
Thanks!
Phil
