HELP! from a Ford tech needed - dragging brakes

**Sonik** · 09-19-2014, 05:50 PM

I'm getting really frustrated with this truck so I want an outside and possibly more informed opinion on the next step.

2003 Ford F150 4WD FX4 130,xxx miles. Truck has 4 wheel discs and dual piston calipers up front. I started having left front caliper dragging occasionally so I pulled it down. Bores looked ok, piston seal and dust boot looked ok, phenolic pistons looked ok and didn't appear to be tight enough in the bores to cause a bind under heat soak. Truck drove great for a couple days, then the following week, the right front did it to me so I repeated the same process with the right front. Drove fine for a few days...same deal again...random caliper hanging...sometimes one, sometimes both. All hardware, sliders, and boots are new, and lubed.

My next SWAG was brake hoses. The way ford does the crimp between hard line and hose can cause a pinch when they start to rust so hoses it was. Swapped, flushed another quart through during the bleeding process and all was good for another couple days until they started dragging again.

There is an adjustable rod on the booster which contacts the plunger on the master cylinder. If this is out of adjustment (too long), it can push on the master cylinder plunger and cause constant brake pressure...so I checked that fit, no excessive contact. SO, I changed the master cylinder Wednesday night (new, no reman). Truck drove fine Thrusday and today to and from work but when I got home and decided to move the truck again to get to another one of my boats, I had to spin the back tires just to get it to move on gravel.

Truck has ABS, no warning light on, and when put into an ABS stop, it functions as it should with pushback and the like. I know very little about how the ABS system on the truck works, but I dont see how it could be the culprit considering the dragging brakes are now random between both front wheels.

What is strange is every time I open the system up to swap a part and/or bleed, it drives fine for a day or so then its back to the same old same old again.

So, my next step is calipers I think. So.....someone with some experience with '97-'03 Ford 1/2 ton trucks, preferrably in the industry, please try to enlighten me as to WTF is going on. The truck 11yrs old, is a solid 9 of 10, and very very well maintained. I mean, seriously, I work on heavy military equipment powertrains for a living so I really get irritated when common sense troubleshooting doesn't reveal an obvious problem. Thx ahead of time for any input.

P.S. - Its really putting a damper on my style as this is my only tow vehicle right now and the wife isn't too keen on me putting a hitch on the new vehicle.

**oldschoolltv** · 09-19-2014, 06:05 PM

Sorry can't help on the brakes but I have the exact same year and model truck since new, with 110k on it, only problems so far are both fr cv boots and now ac clutch is making a lot of noise, curious what you find on the brakes. Matt

**albypine** · 09-19-2014, 06:35 PM

Call me . Before you f everything up and toss money at it that it does not need

**Sonik** · 09-19-2014, 06:45 PM

Gimme a couple hours. Date nite with the wife. I'll text ya when I'm home.

**albypine** · 09-19-2014, 07:08 PM

Bic lighters use to be .99 cents

get ya fixed up

call me when your done with date night

**dumbnfun2** · 09-19-2014, 07:50 PM

Just put a new caliper on side that's hangin ....

**Sonik** · 09-19-2014, 08:31 PM

That's the problem......I can flip a coin as to which one will drag on any given day.

**dumbnfun2** · 09-19-2014, 08:37 PM

Swap em both out .... Can't b more than 50 a piece ....

**transomstand** · 09-19-2014, 09:27 PM

Wonder if you got the dreaded brake hose check valve syndrome goin on.

**Sonik** · 09-19-2014, 09:34 PM

Elaborate. Better yet, it's been a while since I've harassed you. Down for a call?

**dumbnfun2** · 09-19-2014, 09:49 PM

Everytime iv ever had a caliper hang up I just changed the caliper ... Then go for the small stuff ... But jmo...

**Sonik** · 09-19-2014, 09:57 PM

I've got a set of calipers on the bench waiting for it. I'm not denying the need, I just don't like the fact I can't rationalize the symptoms beyong a guess at this point....I'm a troubleshooter more than a parts changer as I like the challenge but I figured I'd give it a shot here and see if someone had some good sound advice (I.E. systemic or engineering shortfall) as to why this is occurring moreso than just replacing parts. I appreciate your input DnF

**dumbnfun2** · 09-19-2014, 10:20 PM

The way I look at it is how they engineer things these days ... Kinda like how they say they just don't make em like that anymore ... Not sure if true but I once heard that Edison's bulbs are still goin ... They engineer things to break ... If it was older car I would think something small ... But if a caliper is hangin up I would just swap it out ... Keeps happening then yeah somethin else ... Iv had a few calipers hang up and that what my uncle always went for first ... That's all ... And my dad is kinda like u ... Likes to take stuff apart and mess w stuff

but most of the time he does more work than it would cost to just swap out the problem part

but I will never say I'm right and someone else is wrong either way I hope it is something simple and u get it fixed and the ol ford keeps ya safe ... Cz I know ur military and u keep us all safe

keep us posted if it ain't the caliper ill ask my uncle what to look for next he was Lincoln mech so are both his sons ...