Tow rig tech - brake bleeding

[Harry]

Dodge Ram 2500

Did a brake overhaul last weekend. Drums turned, new shoes, new calipers, new front hoses. Wheel cylinders, pads and rotors are a year old.

Bled, and bled, and bled. Cannot get pedal to come up hard and stomping the pedal at speed results in a quick chirp of the front tires as the pedal goes the floor. Feels spongy. Assumed master cylinder, got a new one. Bled, and bled, and bled. No difference. According to part numbers, I bought 8800gvw master and calipers and my truck says 8800gvw inside the door. Drums are adjusted correctly.

If I clamp the hoses with vice grips right before they go into the calipers and turn the truck on and hit the pedal, it comes up nice and firm like it should. Based on this, seems to me that one or both calipers are causing the issue... And not the hoses or master cylinder or anything else. But how? There is no leak I can see anywhere. I can watch the caliper move on the sliders and they can easily be moved by hand in and out when taken off the knuckle.

I am just flat out of ideas. Should I just go try another pair of calipers? I'd really like to understand what the problem is here...

[Magilla]

1 did you spin the rear adjusters out until the shoes drag on the drums?

2 did you bench bleed the master?

[Harry]

1. Yes

2. Yes

[Harry]

Rear abs bypassed. Switched back to old calipers. No change. Ready to burn it.

[Harry]

I'm at a loss. Does anyone have a recommendation for a shop on this side of the river? I of course need it done before Thursday.

FML

[CumminsJeep]

Im at a loss. I remember I had the same problem when I put my 8.8 in until i realized I had the calipers on the wrong side and the bleeders were on the bottom

If you crimped the lines and got a firm pedal, its gotta be something at the wheel end like a caliper, wheel cylinder, shoe adjustment, or trapped air somewhere. If it was a master or booster the pedal would sink regardless. You can always crimp off individual lines and see if you can pinpoint it but it sounds like you already did that. Good Luck

[Luke95]

Did you try gravity bleeding them? My friends 1500 dodge needed that for him to be able to get the pedal firm.

[Harry]

Yes, and have done every other brake bleeding technique I know of.

Going to try to hunt down a NEW master, one I have now is reman. Still not convinced that's the problem, but the symptoms are just to weird to blame on a set of obviously non-leaking calipers...

[Harry]

New master in and system bled. Pedal still feels like shit but sinking is gone and front tires will lock up at 45mph with pedal stopping at about 3/4 travel. Better than a quick chirp as the pedal goes to the floor. Not convinced its right, but improved enough for use I suppose.

[customcreationsllc]

Are you getting air out?

Are the calipers or wheel cylinders upside down or on the wrong side?
I've received two of the same side calipers before.
You can bleed the calipers off the car with a block of wood or a clamp.

you said the pedal is hard when you clamp off the hose? Then the from that point back should be good.

I took a piece of line and welded it off and I used that as a plug.

If you plug off the lines and the pedal is still soft then plug off the master, if it is still soft then the master is bad. I've had bad new masters before.

I don't know what the tuck looks like without seeing it.

I've used larger wheel cylinders before they bleed just fine the only issue I had is that they bent the crap out of the shoes.


Good luck

[Harry]

Bleeders are all at the top. New master seems to have them back to Dodge level of acceptable. Not sure if I bled this master more thoroughly than he other or if the reman actually was bad.

[Customjob]

I have a vacuum bleeder. I have bled brakes for people who have tried and tried to manually bleed them with no success and they turned out great. just my two cents. plus you can do it by yourself.