Dragging front brakes help- long back story

While doing ball joints and steering linkages on my 96 F250 (2wd diesel) I found that I needed front brakes in the worst way. Like the pads were worn to the point I wouldn't have made it another week without eating a rotor. The calipers were ugly but seemed serviceable. The truck had been stopping decently, the pad wear wasn't badly mismatched in/out, and the pistons compressed just fine with c-clamps. I figured I'd at least give them a shot. I put the truck back together and before putting the wheels on I pumped the brake pedal until the new pads made contact with the rotors and stood on it a couple times to seat them well. When I tried to turn the hubs by hand before installing the wheels, I couldn't. The driver's side could be turned by putting a hinge handle in the lugs and pushing pretty hard. The passenger side wouldn't turn even with the hinge handle. Crap, I though, guess I do need calipers.

I grabbed two reman calipers from the local shop and bolted them on. The passenger side reman bracket had bad threads I didn't catch and it seized the bracket bolts half way in. I ended up cutting the bolts out with a sawzall, buying new bolts from Ford, and using the original bracket with the reman caliper. Bled the brakes old school with my wife pumping the pedal in the truck. Still had the same problem although it was better. I could just turn the driver's side hub by hand and could turn the passenger side easily enough using a hinge handle, but not by hand.

I have seen old ford trucks with a brake locked down by a deteriorated hose, so I figured that must be my problem. I replaced both hoses AND the master cylinder just to be safe (parts are relatively cheap.) I bought copious amounts of DOT3 and (after bench bleeding the MC) used a Motive pressure bleeder to flush/bleed the entire front system.

This got me to the point that I could drive the truck, sort of. The driver's side is pretty much fine. I could spin the hub by hand although there's resistance. The passenger side could be spun but it took a good bit more effort than the drv side. I figured, hey, old truck, they probably need to wear into the rotors since I didn't turn them. It'll sort itself out soon. I drove the truck about 6 miles to work and about 15 miles over to a friends house and back. Through all this the psgr side wheel would be a little warmer than the drv when I'd stop, but not HOT like I've seen when a caliper is really locked down. I could easily keep my hand on the lugs. I took the truck to the alignment shop since I'd done all the front end work, and they aligned it but noted it was pulling right because the brakes were dragging. Driving the truck after having it aligned I realized how much of the pull was from brakes before. Something still wasn't right.

After much thought I decided the passenger reman caliper must have been bad. Looking back, I don't think it's a hydraulic lock issue because you can open the bleeder valve and the caliper doesn't back off. It must be some sort of mechanical issue on the caliper itself, plus that side was a reman caliper mounted to a factory bracket which should be fine, but maybe there's a bind. The caliper slides seemed okay through the whole affair, but who know. So I warrantied the caliper and put on another reman caliper, this time with the supplied bracket.

Now the truck drives -almost- fine. It's still pulling to the right a little but it's not bad. The passenger side hub is easy to rotate by hand but still has a little more drag than the drv side.

The only component on the front brake system I haven't changed is the Rear ABS proportioning unit and the hard steel lines. The RABS would affect both front wheels equally if it was a problem, besides which releasing the hydralic pressure on the caliper doesn't change anything, so I'm pretty sure it's nit a hydraulic issue.

The new pads do contact a slightly different area of the rotor than the originals, so they do drag just a smidge in a rusty area. I would expect this to be the same on both sides but I can't say I looked that closely at the driver's side. I would also expect this to self correct as the pad wears off the rust.

What the hell am I missing?

And BTW, if I ever catch the sumbich who thought lock tite on brake line threads was a good idea, you guys will have to go my bail money.

My '98 e250 work van went through a few front calipers in the 4 years that I had it. Both factory original calipers failed before 60k miles. I'm willing to say that the calipers are a problem area. Just replace them (again).

I have a hard time believing the odds of getting two bad calipers right out of the box back to back. This whole affair has only been over a week, it's not like the new (reman) ones have more than about 20 miles on them....

If I remember correctly there were Ford trucks of that era where there were different inside/outside pads that look the same at a glance and fit interchangeably in the caliper but can cause issues like you're having.

In reply to NOT A TA:

Huh. I'd swear they were all 4 the same, but it's worth a check. Do you remember what was different? amount of pad, position of bad on backing, etc?

Also make sure the pads slide around nicely on the brackets. I usually have to file/grind the metal part of the pad to get them to not have stick. Then I put some antiseize in there tracks. Those are stamped on a press and many times you will find a burr on the edge making them bigger than they should be.

Co worker suggested that worn wheel bearings might have enough play to cause the brakes to drag. Although the bearings on the passenger side were obviously older than the driver's, there was no play in the hub once they were tightened. If it were worn enough to change the hub angle enough to drag the brakes, wouldn't you feel some free play in the hub?

gearheadmb - good thought on the pad slides. I'll have to double check that.

I doubt wheel bearings are your problem. I once worked on a Cummins truck that play in the wheel bearings made the rotor push the caliper piston back in, causing a deep pedal. If the bearings were so tight to cause a drag they would have completely locked up or dumped the wheel off the truck by now.

All right guys, update. I took everything apart. Checked pad slides, they're good. Checked wheel bearings, no play. Checked the caliper mount ears on the spindle, not bent.

I did notice that the DRV side caliper was a different type of casting than the PSG side. I bought another DRV side that matches the psg and put it on. I thought maybe the odd casting was some different spec that had different piston retraction for the same pressure. Guess not, it's the exact same.

The only thing I haven't replaced is hard lines. There's 1 hard line from the MC to the DRV side flex hose. At the flex hose connection a second hard line connects and runs under the engine to the PSG side flex hose. So both front brakes should be experiencing the same line pressure. Is it possible that the hard line to the passenger side has crud in my acting as a check valve? Do they rust internally and look fine outside?

HELP! I'm reaching the end of my tether on this.

Up here in the Northland with 6 months of winter and so much salt applied to the roads they are still white after snow and ice melts, rust and rust jacking causes brakes to stick and/or lock up. Cleaning all parts that are supposed to move on application and release (pins, shims, pads, bridge, bushings, bolts, mounts and calipers) are cleaned down to the bare metal and lubricated with synthetic high temp brake lube. Should be done once a year (spring) whether it needs new brakes or not.

Are the pads grabing an un worn section of the disk? rust groove left by the old pads?

You said opening the bleeder valves to release any pressure at the caliper doesn't change anything, right? If a bad hydraulic part was having a check valve effect, you should get fluid squirting out when you open the bleeder valve.

44Dwarf wrote: Are the pads grabing an un worn section of the disk? rust groove left by the old pads?

a tiny bit, yes, but only like 2mm on the inside edge, and it seems the same on both sides. I even swapped pads side-to-side in case one was off a little. I don't think it's enough to cause this. If so driving it should straighten out the issue in time.

GameboyRMH wrote: You said opening the bleeder valves to release any pressure at the caliper doesn't change anything, right? If a bad hydraulic part was having a check valve effect, you should get fluid squirting out when you open the bleeder valve.

That was my thought too. I don't get that. I open the bleeder and some seeps out, but no squirting and it doesn't change the amount of drag. The brakes are dragging but not really locked down. It seems like if the hard line were only partially obstructed it would equalized side-to-side over time. Like you could let the truck sit and eventually it would bleed off and both wheels would drag the same. That's not the case here.

I'm thinking my next step may be to pull the rotors and have them turned. You know there is only one shop locally that turns rotors, and it costs $20 each? Boy times have changed.

My bet is partly bit crust on rotors and partly bit pads hanging in the slider. file the slider or the pad. I'd rather do the slider as the pad has paint to keep it from rusting down the road, but quicker to do the pad.

On pad fitment,make sure those slider tracks are CLEAN, rust scale can looks a lot like metal and won't come off without some hammering or serious powered wire brush work.

In reply to BrokenYugo:

Die Grinder w/medium sanding pads and good flat file for the flat areas. Clean the excess paint from the pads where they slide in caliper and bridge. Synthetic brake lube will deter future rusting for a while.

The pad slider tracks are replaceable stainless steel clips. New tracks come with all pads. These are fresh, shiny, and slick. All pads move beautifully on the sliders.

The caliper brackets that the clips seat on are also new. There is no rust on any part of the caliper, at least until it rains, because it's all been replaced. Twice. On each side.

I didn't see where you said you greased the pads. If not and you have the SS holders it is important. If I reuse the brackets I clean the rust where the holder goes down to bare metal.

Disc brakes release when the vehicle moves. The engine has a lot more power than your hands so not being able to turn them by hand is normal. Drive it and see if the wheels/hubs are hot on one side. If so then you have dragging brakes. Another symptom of dragging brakes is tire vibration at higher speeds.

I've been driving the truck off and on and it's still dragging. Not bad enough to get really hot, but enough for a slight pull to still be there if you take your hands off the wheel.

For diagnostic purposes, can you switch brake rotors side to side on these trucks? The wheel bearings are in the rotor and have an undetermined but significant amount of miles on them. I'm thinking about swapping the rotors left to right (with their associated bearings) to see if the drag moves with the rotor. Any issues with directionality of the bearing rotation or mating to the spindle?