I have a 2002 Ford Ranger 4x4 with ABS. The brakes are very inconsistent.

First problem was the dreaded ABS would kick in when I was slowing down to stop. The front ABS sensors went bad and the Ford dealership suggested replacing the hubs. I did that and all was well. (trying to get through winter without massive repair)

Now when I hit the brakes the rears might lock up, or the truck might just slow down while I am braking hard, or it works normal.

When I replaced the hubs I noticed my rotors and pads where bad. So I replaced the rotors, pads and bought rebuilt calipers the following week.

Truck seemed ok and no problems for about a week. Then the same issue appeared.

replaced the rear pads 25K ago so decided to check them. One emergency brake bar was frozen ruining one shoe. Didn't want to fight the rusted bleeders so I bought new wheel cylinders, new shoes and had the drums turned.

tested the truck again everything was fine for about 1 week then same issue.

I had a car that experienced similar problems and it was solved with a new master cylinder.

This weekend replaced the Master cylinder. Road tested everything was fine
now driving to work, the brakes again become inconsistent.

The only thing left is the ABS motor/module. I don't see a proportioning valve in the system. Would this be a symptom of the ABS motor?

If not any suggestions?

I would think if the sytem was not bled properly the problems should show immediately not 1 week later

 

Should add
I am the sole driver
Bought the truck new.
Currently has 64,000 miles

 

Check the rubber lines!! If they are swelling when you press on the brake you are
not getting all the power to the pads. If a solvent or something that didn't agree
with the rubber lines caused them to degrade, they could at certain temps get too
soft and give you trouble. Be sure to take apart and grease the self adjuster on
the rear brakes and always use a high temperature grease on the contact points
where the shoes hit the backing plate, the WC contact points basically anything that
moves. Of course the calipers need to have lubrication on their sliding points.
What kind of brake pad material are you using? If you are using organic and do alot
of stop and go or towing and heat up the brake pads they are not designed for that
and you would do better with semi metallic and versa vice!! If you are running some
metallics and you normal drive on the highway and the brakes have time to cool down
between uses they will not react the way you expect and can be dangerous in either
circumstance!!

 

I have EBC green on the front and the standard Autozone shoes on the back. Don't use the truck for towing - just winter driving and hauling my dogs around. The problem started with the original Ford brakes so my choice of pads really should not affect that.
Temperature doesn't make any difference.

Did think about the hoses swelling but would think that should create a consistent problem.

Also wonder when the rears lock (not very often) why the ABS doesn't release the preasure