Need Brake help on Dodge Little Ram truck

[TowPro]

My brother got this older little ram truck (I think its called a D50) from his mother inlaw. I think this is a mistubishi truck?



anyway, the Front Calipers lock up.



so far it got a new master cylinder (2 or 3 years ago)

New Calipers a couple months ago with new pads and all hardware. I think it worked OK for a couple months after the Calipers were replaced but it never got driven much more then 10 miles per trip.



Now it is starting to lock up the front Calipers again In fact it gets so bad the other day he was in went out to get something, came home and went into the back yard. The LF tire was skidding in the mud as the truck tried to move.

This is when I got involved. I felt the brake pedal was to high so I adjusted the master cylinder push rod (thinking maybe it was not allowing the master cylinder to return all the way). Made no difference.



Next I think I will pull the Calipers and see if they are real tight.



Any ideas?

 

[seemore]

I'd replace both front brake hoses!

 

[B.G. Smith]

seemore may have the answer. I would open the bleeder on the calipers and see if that releases the brake. If so, then the hose would be suspect since you have already checked the piston rod clearance on the master cylinder. Dodge had problems on some of their front calipers on trucks a few years back, they came with phenolic pistons in the calipers and would lock up after a while. If none of the other stuff works might be worth looking at. Back then they had a replacement cast iron piston. bg

 

[TowPro]

Once I get it in the shop I will check it out. Since he bought the calapers at Auto Zone they have a life time warrantee. I guess it can't hurt to replace the hoses either since they are over 20 years old. Time is the only thing standing in the way (I don't have enough time to get it in the shop). The truck is really an "extra" truck for them (he drives a 04 Ford 6. 0, he needs an extra truck!)

 

[AKAMAC]

Make sure the vacuum assist is not hanging up. My Plymoth Arrow acted like that when I had water get into the system.

 

[TowPro]

AHAMAC, do you have some more info on this? You mean the vacuum container that is behind the master cylinder got water in it? How did you get water in it, and how did you fix the problem, remove and dump or remove and replace?

How did you know this was the problem, Did the pedel not return all the way?

 

[AKAMAC]

The pedal would firm-up and brakes would hang. I got another from a wrecker and replaced it. I figured it out by shutting doun truck and letting the vaccum bleed off to release the brakes.

"How did you get water in it?"

Do I really need to show what a dumb-arse I was at 23.

<hint> Flooded parking lot, power slides... ...

 

[TowPro]

you know I bet your right! It had a dead battery so he jumped it, moved it into the driveway and let it run for around 1/2 hour. when he came back outside to park it the brake pedal was hard as a rock and the truck was stuck like the emergency brake was on! THis rules out heat causing the calipers to lock up!

 

[TowPro]

We finally got around to putting the brake booster on. Now you can let the truck idle for a long time and the brakes will not stick.



So I went out and drove it, Yes the calipers get hot and tight. Just opening a bleeder screw will let off pressure and the caliper releases.



Then he tells me that someone else in family several years ago put power steering fluid in the master cylinder



I saw the cap of the master cylinder; it’s all deformed as if something caused it to swell.

So I am thinking the master cylinder inside parts look just like the cap.

I think they are swelled, but still push pressure when you stand on the brake pedal. Then when you release the pedal, the swelled rubber in the master cylinder covers the ports and the fluid cannot return.



Even with a vacuum bleeder on the caliper, I could not suck fluid through the system.



I told him to get a master cylinder. Hate to say it but I think he should also replace the hoses. I went to napa.com and looked up a replacement MC. It warns, "Do not use petroleum products in this because it contains rubber. "

I am pretty sure power steering fluid is petroleum based.

 

[bmoeller]

I used to have a Mazda B2000. Had one of the front wheels lock up. The caliper piston was sticking. Replaced it, and that was the end of that problem.

 

[PToombs]

If it had power steering fluid in it all the hoses and cylinders/ calipers need to be replaced. And the whole system needs to be thoroughly flushed. (before new parts are installed!)