The story:

Okay... I was driving in farm country about 30 miles west of Minneapolis today, looking for photo opportunities. The truck felt sluggish and really didn't want to go over 60mph. Every time I came to the slightest hill, the torque converter would unlock and it felt as though the truck were pulling to the left from time to time. I thought it may just be the wind until I began to smell something like plastic burning. It turns out that the paint on the driver side caliper is what smelled so bad. The caliper was stuck and getting hot, but didn't escolate into smoke. It's not stuck so tight that I can't drive, but tight enough that the truck won't roll down a hill or move unless I give it gas.

So, what do I replace?

The pads and rotors only have maybe 2,000 miles and there's no pulsation so I don't think the rotor is warped. Right now, I'm not planning on replacing the pads or the rotors; Just the caliper or perhaps only the pistons.

A premium caliper from NAPA is around $100.00 + a $55.00 core. A caliper rebuild kit is just $15.00 from Ford.

Anyone ever rebuild a caliper? I figured the kit would have the pistons and seals, which is all I need. I noticed when I did the brakes last summer that one piston did seem to stick a bit so I'm sure that's were the problem is.

 

Before you buy new calipers, check the caliper slide bolts. Remove them from the bracket that holds the rotor. They are the ovals with the rubber boots. Clean them and their bores with a degreaser and sand them with 500 or so grit paper. Put synthetic hi-temp grease in the bore and you should be good to go. The caliper itself is not bad until the rubber seals around the piston are shot or it can't be pressed in with a C clamp and a block. I would also do a bleed later just to be safe. It should be every year on the 97-01 I believe. Try it, $2.50 of purple power beats a $250 brake job for calipers because the get replaced in pairs (ABS). Good Luck.

 

AJ,Autozone has remanufactured calipers for $40.00 each.

 

I'm still not sure what happened....

When I backed the truck into the garage last night, the caliper was no longer froze. I checked everything out this morning and it all seems to be working properly. I compressed to pistons, cleaned and lubricated the slide pins and bled the brakes. I dunno...

It's too damn cold and depressing out there, even with the heater. I'm just going to see what happens and if I still own the truck in the spring, I think I'll rebuild the calipers and replace the brake lines then.

Thanks

 

Anyone else have any ideas

Yesterday, I replaced the calipers with rebuilt Ford calipers from NAPA. Both front brakes still drag, so today I replaced the brake hoses, thinking that maybe they coulnd't hold enough pressure retract the pistons. The brakes still drag... It's not so bad that the truck is undrivable; The brakes and rotors are not overheating. It's just that it doesn't feel right.

Does anyone have any experience with a bad master cylinder not releasing pressure on the caliper pistons? Both front brakes seem to have equal drag, whereas the rear brakes are fine. The brake booster also seems to be working fine so the master cylinder is my only other option to throw at this

 

AJ,

What kind on temps are you having? My thoughts are along the lines of moisture in the brake fluid, but if you have replaced both front calipers than a good portion has already been changed.

Just a WAG.

 

It's cold... I've wondered about the fluid as well, but I completely flushed all of the lines during the summer so the fluid is fresh.

hmmmm......

 

Un-Stuck it!



Did you inspect and/or replace the slide pins when you replaced the calipers? You've got a classic case of stuck slide-pins. The reason it got better was because it cooled off when it sat, gaining some clearance between the pad and rotor. As soon as it gets hot again, it'll likely do it again.

Let us know how it works out.

-Joe

 

It's not the slide pins. The problem is that the pistons are not retracting back into the calipers enough to release the pads.

Originally, it was worse on the left side, but now there's equal drag on both sides. With the wheels in the air, it will only spin about 1/4 turn before the drag stops it. The rear wheels are not affected at all.

The booster is functioning and the pushrod is adjusted so I do think it's the master cylinder. I think the master cylinder is not allowing pressure to be released on the front calipers for some reason. The master cylinder should act as a vacuum to pull the pistons back when I release the brake and it's just not doing this.

 

If I were you, I'd replace both calipers. If one is bad, the other one is probably not to far from going bad. You can get them for about $40.00 each. Not too much to pay for a safe vehicle.

 

They've already been replaced.

 

i suppose you have already elimated dragging from the rear brakes and/or emergency brakes. Cold weather could be affecting them as well.

 

False.

The master cylinder should not pull the pistons back into the caliper. Otherwise, there would be a gap there that would have to be closed before the brakes would begin to slow the vehicle. The master cylinder should release the pressure, and if there is any runout at all in the rotor, it may slightly push the piston back into the caliper, and the pressure relief on the seals may allow the piston to retract ever so slightly, but they should not retract into the caliper bores by any means. They should simply stop squeezing the rotors.

The only way the master cylinder could hold the pressure is if the master cylinder piston was not retracting past the compensator port. Pop the cap off the master cylinder, remove the little screen filter and have somebody actuate the brakes.

Per the '01 manual:
If you adjusted the push-rod out, that could be the cause of your problems if it was adjusted to the point that it's not letting the master cylinder fully return past the compensator ports and bleed off the remaining pressure in the system.

If the brakes were holding pressure on the fronts, you would know it. The rotors would be discolored and smoking in just a few miles of driving. Also, if it was a master cylinder issue, it would happen to BOTH front calipers or both rear calipers, or (more likely) all four would be dragging.

-Joe

 

I agree with Blueovalfitter. Instead of rebuilding my stock one, I bought one from Autozone for about $40. My calipher was sticking periodically until finally it locked down. I bought one from Autozone and had it on and operating after bleeding in about 45 minutes. Beats rebuilding and taking unnecessary risks! Good luck!

 

Are you sure that your perportioning valve isn't gunked up and it's freezing up on you?