FRANKV569

.... i m no expert brake system man - so, i thought id ask those of you who are. here goes: i replaced the two rear brake cylinders today on a 2000 ram 2500. when completed, i went to bleed them by having an assistant work the pedal while i did the bleeders with a hose attatched sitting in a jar of brake fluid. i cannot seem to be able to get all of the air out after bleeding each side for about a total of a half hour a piece. it was my understanding that i only needed to open the affected lines ( bleed the new wheel cylinders only). is that correct? or, did i push air all throughout the entire brake system? i have also read about bleeding all of the brake system components in a specific order - like combo valves, master, rwal valve, then wheels. does this or any part of this apply to me? should i try to let the system gravity bleed itself after all the previous bleeding? does gravity remove all trapped air - or, do you still have to bleed? when i was bleeding it earlier, i started with the right rear- then the left rear. i started alternating after awhile - like every 5 mins or so.

jrs_dodge_diesel

The normal procedure is too start at the farthes point from the master cylinder and work your way in. So for us that would be right rear, left rear, right front, left front in that order. When you bleed you need to close the screw before the pedal goes back up. Very important. If you don't do that then the air goes right back in rather than out. Gravity bleeding does not work well, too many bend in the lines and places for air too get trapped, you have to force it out.

You might want to get one of these. Works much better and you don't have to touch the pedal. Click here.

One more thing, if you use the peadl technique DO NOT push the pedal all the way to the floor. The O-ring seal on the piston in the master cylider can rupture if it goes past its normal range where there might be corrosion built up on the cylinder wall. I learned that the hard way my self, cost me a new master cylinder and 2 hours more to put it in.

FRANKV569

thanks for the info. but, do i have to bleed all of the wheels since i only changed the rear wheel cylinders?

Jambbii

I just did the same thing, I put in new rear wheel cylinders also. I just graviity bled them (open both of them up and let fluid run out) Then I just had my brother help me give each side 2 normal bleedings. No air for me and I didnt touch the fronts.

winkle

Are you that brake lines are seated well and tight in the new slave cylinder's, sound like it might sucking air from somewhere.

FRANKV569

yeah, i was wondering if i could do the gravity bleed since i already started bleeding them. as far as the lines being seated, i believe they are. i make sure that i can easily screw them down 5-10 turns by hand to make sure they are not cross threaded. and i have no leakage whatsoever from the fittings. i was wondering if air would be able to travel up to the front from either sitting in the lines -or, me bleeding them. or, at least, would i have to bleed any other components of the brake system . i mean, from what im reading, to bleed the system properly, you must bleed all valves, etc. does that mean that air is traveling further than i think? if i am told to bleed the front calipers too from only replacing rear wheel cylinders- wouldnt that mean that other components between th e two would need bled as well? my own common sense says if i only replaced rear wheel cylinders, bleed only the cylinders. b ut, i just wanted to make sure because i hate ''mystery air'' showing up in the brakes when towing.

infidel

You should just have to bleed the rears unless the master cylinder was allowed to go dry, then you'll have to bleed everything.

KATOOM

Not saying you dont know how to bleed brakes but how do you know your still getting air? Do you have a clear rubber hose attached to the bleeder? Is the person pushing the pedal waiting for you to close the bleeder valve totaly BEFORE the pedal is allowed to move back up? You dont need to bleed the entire system and given your only changing the last item on the brake line there cant be any air to bleed but the air in the cylinder. It isnt a complicated job but doing it wrong can lead to hours of work. Hope you get it figured out.

FRANKV569

i appreciate all of the responses on such a relatively easy task. well, im actually using a piece of small, unused fuel line that is clean. i didnt actually have any clear left. i didnt figure that it mattered since i can see the bubbles still in my glass jar of brake fluid that it is in. my helper is well versed - we've done this before on different vehicles so he knows not to let up on th e pedal til i give him the ok (one thing i never thought much about was not pushing the pedal past the normal position). i can tell you that the bleeders are actually a pain in the asp to operate with a wrench while the hose is attatched. when i think about working on rams as compared to other vehicles ive worked on, i generally think its prett y easy and alot of room underneath - bad design/placement/ or length of the bleeders or something i guess. well ,i may figure it out later - hopefully . if not, dont drive in front of me ! ! just kiddin, just kiddin.

jrs_dodge_diesel

Frank, check out the link in post #2. That little gizmo will pressurize the fluid in the Master Cylinder so you don't have to pump the peadl, you just crack open the bleeder srcew. It beats the crap out of vac pumps.

Stamey

When I installed my new Big-Honkin' wheel cylinders a few weeks ago I JUST gravity bled it. For years I went through all that pumping mess, but finally learned. Just open the bleeder screw and wait, watching the master cylinder so it doesn't get empty. About 10 minutes later I checked them and no air bubbles were coming out so I locked them down and all's well.
I have a high, solid pedal and the brakes are great.

Chris