Ford Chassis 2001 Fleetwood Tioga newbrakes locking .HELP

[Laurielr]

I just bought a 2001 Ford Chassis Tioga, class c.. On its first long distance trip in mountains it didn't seem to have much power intermittently going uphill. One moment it works and one it seems to be having trouble. It was looked at and it was deemed front brakes had locked up and burnt. The front pads, rotors and calipers were all changed and when that didn't fix problem, a subsequent stop had brake hoses and flush done along with rear pads, rotors and calipers changed. 30 miles later, the same problem was encountered...it appears something in braking system is occasionally locking up and not releasing thus making brakes become super hot and other times it drives fine. I am desperate to find some information on it. I just bought this motorhome and it has 28000 miles on it,it was not driven a lot in its years Inspections prior to purchase revealed no leaks or brake issues. Any help would be greatly appreciated.

[j-d]

Thought it must be E450 since you mentioned Rear Pads and Rotors. The E350 didn't get rear disc till a few years later.

To navegator's point about ABS - I've done a goodly amount of brake work on our 2002 E450 chassis but have NOT replaced the Master Cylinder. Only Calipers and Hoses. I was able to flush and bleed the system by siphoning the Reservoir to Empty but NOT the chambers and didn't step on the brake till the Reservoir was full of new fluid. Then I bled the calipers, being careful to never let the Reservoir go dry and put air into the chambers. I this kept the ABS unit "wet" through the process. My understanding is that it requires a special scanner to analyze the ABS, and even to bleed the system if it gets air in it.

The possibility of binding brake pedal pivot or linkage is real. I haven't seen it since an old Dodge we had, but doesn't mean it can't happen. IF IF IF the pedal doesn't return to fully released position, then those little pointed ports won't be open to the Reservoir to let the pressure escape and brakes will remain applied.

[Laurielr]

J-D it is an E450 Chasssis

[navegator]

Check the ABS antilock mechanism, they can do strange things.

navegator

[j-d]

Which Ford Chassis is this Coach on? E350? or E450?

[j-d]

Your brake master cylinder is actually two cylinders in one, with a common fluid reservoir. One cylinder applies front brakes and the other applies rear, both when you step on the brake.

Each cylinder has an inlet port to get its fluid from the reservoir. It has an outlet that goes to its respective front or rear brakes. It ALSO has a little VENT port, to make sure any fluid returning from the brake, when you release it, gets back into the reservoir and does NOT leave that brake applied.

It's only a pinhole, and I've had one "heal up" with corrosion. It would slow the car down on the open road. One time it stopped the car. When I got out, both front wheels were like walking past BBQ grills.

Replacing hoses is a good idea, and it's good you did it. But in this case, I agree with others. I agree that it's a common problem source, and I've actually had it be a plugged port in the Master Cylinder.

I fixed it after two dis-assemblies. First time I missed it. Second time I saw that a little "spot" in one cylinder chamber matched a little hole in the other. A wire wouldn't poke through. I used a small "number drill" and ran a hone over the bore surface. That was to make sure I hadn't created a burr to nick the sealing surface of the rubber piston cup.

Found you a diagram to show what I'm talking about.



The Pink and the Green Chambers/Circuits have two passages each, coming down from the Reservoir. Notice how the RIGHT one in each pair is drawn coming to a point at the bottom. That represents the pinhole that I think is blocked in this RV's master cylinder. If that hole is NOT open, pressure can remain in that brake circuit. The hotter the brake gets, the more the fluid expands, the more unintended apply pressure goes to the brake calipers. BOTH of them.

[Laurielr]

I would add that the gentlman now driving it indicates he drove all night without issue, it appears the problem so far is localized to the system just overheating in the heat of day....and has recommended finding a way to cool the area underneath somehow????

[Tiger02]

Typically it will be one side or the other getting stuck, which will cause the vehicle to pull left or right. This is usually the slide pins in the brake calipers causing this. In rarer cases the flexible brake lines deteriorate from the inside and can cause a check valve type issue so that the brake doesn't release on that side. Sounds like you've changed out all those parts.

The only time I have heard that both front brakes were dragging was due to a brake booster issue. In that issue the poster said he could see the rod between the brake pedal arm and booster get sucked in when starting the van. The link below may be a better place to ask your question to a wider audience.

FTE Link

[enblethen]

Your signature doesn't say what year of rig. Good to put that information there.
You should look into replacing the lines.
Does the rig have ABS?
Yes, it could be master cyclinder.

[Bordercollie]

Is the rig new or used? Did you have front flexible brake lines replaced?
We had a front brake hose collapse internally causing steering problem on an old Chevy Class C. If entire brake system has been checked/parts replaced, etc. and problem still occurs, contact Ford Customer support by phone.

[Travelin2]

If it was one single brake not releasing and always the same one I would suspicion that the pistons in the caliper were seizing but since it is both front brakes doing it at the same time I am more inclined to suspicion the master cylinder.

[Laurielr]

I appreciate this, would this be commmon just based on usage and grade of mountain, or is there something to fix this...since everything is brand new, if we continue, the brakes will likely burn out again without constant monitoring. Thanks for the insight.

[enblethen]

Could be the brake lines collapsing on the inside. Common when front discs overheat and boil the fluid.