It has been an issue since I bought the truck, but it isn't my DD so I eventually replaced all the hardware shoes and drum. Still did it. Took it into a Ford Dealership and they said it is the ABS Hydro Control Unit? Part # 3L3Z 2C286 AARM Supposedly an internal valve is sticking.

When I pull up this part number, it shows that it is the ABS HCU unit for a Ford van? I have toyed with the idea of just pulling the ABS fuse and seeing what happens.

I want to buy another one (it would have to be used since apparently this part isnt made anymore?) but other than a bone yard have no idea where to pick one up. I would rather purchase one that was probably going to work vs. a bone yard one that might have the same issue... Or maybe this is a one off?

Thanks for your help.

 

If they are reading a CODE which tells them the ABS unit is bad... OK........ if they are guessing , I would verify correction operation on both sides.


You should be sure ALL parts on the rear are functioning correctly... There is NO WAY for the ABS to apply ONE rear brake and not the other.. Either they BOTH are trying to engage, or there is a mechanical drag at one rear wheel.

 

I agree, both should be trying to lock up... but just one does. There was no ABS code for them to read and the light on the dash is functioning properly. Should I take it to another Ford dealership for a second opinion? I've checked for pinched lines, replaced all the hardware.... twice. I am kind of at a loss where to move to troubleshoot now.

I appreciate your response!

 

Check the axle seals? I know gear oil will make drum brakes become very grabby, not sure how it affects discs though.

 

Replaced both sides already....

 

What are the chances it could be the brake shoe cable itself? How would I got about testing that?

 

If you feel the park brake adjuster cable is too long check the guide it rides on. Sometimes the guide's protrusion that sets in the brake shoe web wears off, the guide drops a bit making the adjuster cable ineffective.

 

Agree +1

Are the original brake hoses still on it?

 

I have replaced that adjuster. I am starting to lean more towards the E brake cable? It does still have the original hoses on it. They appear to be in good condition. I suppose those are worth replacing as well if I do the cable.

I just don't trust the ABS module diagnosis...

 

There have been occasions where one of the front hoses on the brakes became delaminated inside and a check valve formed.. You can apply the brake, but it will not let the fluid back out to retract...... that's why PDQ asked about the hose. rare, but does happen.. normally it makes the brake NOT BACK OFF when released.

 

Did you replace all the hardware, shoes, and drum on both sides? I'm assuming you did but your initial post indicates possibly just one side. I have 97 and have had this same problem off and on for the last 20 years of owning it. With 200k on it I've replaced the rear brakes 5 or 6 times and I can say that some brands/quality of shoes have caused this problem with me. Replace with something else (brand) and could go literally years without issue. Just something to think about....

 

When I left off the brake, it unlocks and the wheel keeps rolling so I am thinking the one way check valve hose idea might be out... And yes I have tried more expensive shoes in addition to changing out both side at the same time.

I was pulling in the driveway the other day in my other car and the headlights shined on the inside of that wheel and there is seepage of brake fluid on it. Annoying.

I appropriate all the help so far, thank you.

 

May be semi plugged brake line. I replaced all in my truck from below driver sit back to both rear brake cylinders with pvf (black ones). Brakes front and rear at my rusty f250 99 work like champs. I have habit of changing brake lines to pvf at any hint of rust.

 

Its puking brake fluid now so I am going to have to give it some attention. I've just been super busy with other things. Going to replace the cable and hose, re adjust and go from there... Probably have to replace the cylinder as well since its probably leaking.