I have a vacuum setup for bleeding brakes and will probably go that route as I have no helper. If I'm starting with everything empty the FSM says to bleed the rear valve first. Then the rear brakes. To do the front I have to use some tool to bypass the proportioning valve according to the FSM when using a vacuum. So a couple of questions...

With my bad back I want to lift the truck to bleed...easier for me to stand than crawl. If I fill up the Mc will there be enough fluid to bleed one device completely...whether the rear abs valve or a single rear brake. Just trying to get a feel for how often to have to refill resevoir.

Second question...what can I use instead of the special tool to hold the front bypass in the correct state to bleed the fronts?

is it necessary to bleed the Mc first? The FSM mentions bench bleeding...really don't want to pull it back out to do so...if it's necessary can't I just route some temporary lines back into the Mc as shown in the FSM and use the pedal to bleed?

 

Rather than worry about keeping the MC full, try a kit like this one from Harbor Freight: http://www.harborfreight.com/brake-f...der-92924.html

Its main advantage is that reservoir bottle; fill it up, put the proper adapter on it, turn it over into the master cylinder, and open it up. It will gravity feed enough brake fluid in so that you can't pull it back dry; the suction reservoir is SMALLER, so once you get brake fluid to the wheel cylinder, stop, fill the reservoir bottle back up, and then as long as there's room in the far end there's brake fluid in the reservoir.

Works a treat for that.

For the other; that, I don't know. From the picture in my FSM, it looks like anything that can hold it open would work. OTOH, you can always put that reservoir in, and let it gravity bleed; that also does not trigger the valve. OTGH, I didn't have any problem with that Harbor Freight unit bleeding the brakes in my Dakota; I bet it'll do the job for you just fine, no need, it'll be just like gravity bleeding. I think.

There's kits that you can use to "bench bleed" the MC on the truck; I didn't have any problem with that vacuum bleeder, considering I also did a few pumps of the brake pedal when done.

RwP

 

I'm about to pull my hair out on these brakes....So, using the help of my son, I did the two person conventional method. Per the FSM, bled the rear ABS first, then the rears, then the fronts. I've gone though almost 2 quarts of fluid. I also put in a new MC and bench bled it properly. After two go 'rounds, I still had mushy brakes. I found a small leak at the rear brake line driver's side, so I cut it off, reflared it, blew out the female connection, and put a new fitting on...New fitting went in much further, easier, so now I have no leak. Rebled again, and with truck off, I have really firm pedal (no boost assist) and solid flow of fluid out of all bleeders (no air). Crank truck, and pedal goes all the way to the floor. I haven't driven it again yet, but suspect I'm still going to have weak brakes. I've tried the reverse stop to set the rear drum pads, but that didn't seem to help before. What am I missing?!? It seems odd that I have nice firm pedal with no Vac assist, but nothing with Vac assist...is there such a thing as too much vacuum...lol. I'm putting out about 18 inches with this motor.

 

No, but there's a bit of a counterbalance within the brake booster; you may have one that's failing on you.

I'd bleed ONE MORE TIME; and if it doesn't improve, I'd then replace the booster.

But when you swapped the master cylinder, did you adjust the push rod? It may be too short right now, causing the booster to travel too far to activate the brakes.

RwP

 

No I didn't adjust the push rod...the MC's appeared to be exactly the same, so I ASSumed it would need no adjustment.

 

Well I drove it for the first time on the highway to the muffler shop...when it was up on their rack I noticed some brake fluid on the rear wheel, but not from the line/fitting...looks like from INSIDE the Drum. KNEW I should have replaced the drum cylinders

 

Sure enough, took off the passenger rear tire and drum and it was full of brake fluid...Took drum shoes out and the piston literally fell apart...one whole end was blown out. Hoping that this contributed to my bleeding issue.

Also noticed that after about a 10 mile trip, the driver side drum was smoking hot....literally smoking. It's not dragging as I can pull the drum on/off without interference. Would the fact that it was doing the only rear braking cause it to heat up?

 

Don't know why the driver side got hot but your deductions sounds right. I wanted to suggest you replace both cylinders. I was 500+ (DOH that's 500+ miles from home) and my rear wheels locked up on me in the rain coming to a stop in traffic. Scary stuff. Turns out some guy had replaced only one cylinder at some point and they were both pretty sketchy, I think one was OE when I replaced them. At around 10 bucks its worth it to avoid having the wheels lock up.

 

Could it be the paint "burning in" on the drum? I wouldn't think it'd get that hot unless it was either dragging a shoe or you have some long down-hills on your way home.

Those wheel cylinders don't like sitting up for long periods. I had one bleed out on mine shortly after rolling the truck into a new location while I was still putting it all together. I'm with onemore94, replace both. With all the "go" your truck has, you want to be sure the binders are at their best.

 

Well the other brake cylinder gave lose today....but it may be a blessing in disguise. I noticed that the MC both chambers emptied when the fluid was going out the busted rear cylinder. That shouldn't happen should it...I thought the reason for two cylinders were so youd isolate front and back in case one failed. So if the MC emptied both resevoirs does that point to a bad proportioning valve?