O.T. 94 Ram 1500 brakes update (long post)

Thanks for all the suggestions. As I stated earlier, it started with low fluid level with no apparent system leaks. I filled reservoir and have had very poor braking with ABS chattering. I got the bleeder screws on the front loose and functional. Yesterday I decided to do the same for the rear. I fought the rusted on rims for about 4 hours before getting them off. I used propane torch to heat and then cool with water, and then the same with atf/mineral spirit mix. The one side came off on the second heating cooling cycle. On the other side I did the same about 6 more cycles and also used BFH on inside and outside. I finally resorted to using a scissors jack between the leaf springs and the rim. I had twisted the jack on the first try with it. I repositioned it and used a 1/2" ratchet to crank it as tight as I could get it. I then heated the rim again and it did pop off. I was surely glad I thought to put a lug nut on as it jumped out with enough force to do bodily damage.
I was not able to get rear bleeder screws loose with the amount of force I figured would not twist them off using a vise grips. The hex should have either been an 8 mm or a 5/16". Neither fit tight enough to keep from spinning on the bleeder. Evidently 22 years of corrosion made them smaller. 7 mm socket is too small. There again I heated and cooled numerous times. By then I had enough for the day and came in for the night. This morning I cleaned up the rear rims and hubs and reinstalled the rear tires after liberally using anti-seize on mating surfaces. I then preceded to bleed just the front brakes. Things seemed normal and I did it several times rotating from left to right. I put the wheels back on and took it for a road test. I actually had made things worse. Now the ABS light is on and does not function. ABS light was not on before. Also the brake warning light on the dash is lit which it was not before. Now the left front wheel locks up on slick surfaces. The overall braking effect is similar, but not necessarily straight. I will probably get new wheel cylinders and some brake line before I go after the rear bleeders to prevent time delays when I break things. Probably be next weekend before I get to it again.
Time to start over. Not sure where to begin.

IA Roy,

I swear if I ever buy a new(er) truck, I am going to put a large wad of sticky grease on those brake fittings.

D.

On a Dodge ram forum, the new problems I have probably are related to not bleeding the rear brakes as well as the front. I will get parts to replace the ones I will probably break when I go there next weekend.

A coating of spray on bed liner would be better because it won't get petroleum into brakes. Jim

Update, I don't know if I made it worse or found the problem. I heated and cooled the rear bleeders and brake lines. I found a hole in the line on one side or made one. That gives me direction on fixing it.

Be sure and check the upper and lower ball joints The ones on one side of my 96 Cummins were bad and was causing a bad shimmy when the brakes were applied,

Getting into ABS and bleeding those systems is kind of technology that's in the "too new for me" territory. I'm pretty sure you need the computer to cycle the ABS to bleed the controller.

If it were me, I'd go ahead and do all the obvious stuff - new lines if in doubt - whatever it takes to make it solid - bleed it enough to work, then bring it to a mechanic for a full bleeding.

Do you have a manual for the truck?

Think you're on the right track by replacing the wheel cylinders. You might find the mystery leak when you pull the drums, could have fluid soaked shoes.

Hello IA Roy,

By bleeding just the front brakes you created a pressure inbalance. The sensor will shut tbe light off once you bleed the rear brakes. It is a bit messy, but you can bleed the rear brakes by using tbe lines going into the cylinders. They will work if you can get them loose. You nay need a fuel line wrench though. What the wrech is basically its a six point box wrench, with just enough opening to clear the line. You may be able to sign one out where you get your parts? If you don't have one. They work good as well for those pesky bkeeders!


GUIDO.

Regarding the brake light now on.
In the combination valve there is a piston that normally has brake pressure on both ends of it, front brake circuit on one side, rear on the other.
When there is a pressure loss on one side it allows the piston to travel from its neutral position which then closes contacts to turn the light on.
Regarding the front brake that is now locking up.
Very unlikely the front brakes have suddenly developed super powers or suddenly started to drag, what happens is your back brakes having failed are not contributing to stopping the truck, because the front brakes are now doing all the work, any variation in traction will cause a situation where the weight of the truck is pushing forward and overcoming the stopping power of the front wheels until one or both start to skid.
If you were to test drive it now with the left wheel on pavement and the right on a gravel shoulder, the right will lock up, drive on the other side of the road and the left will lock up.
You are on the right track getting new lines and wheel cylinders, once you get the rear brakes apart and repaired as needed there is a good chance all will be good.