Ok, so I have had every malady that these trucks throw at you in the way of brakes. I have gone through and replaced every item in the system, except the front calipers. The fronts have never given me any indication of problems. After replacing the proportioning valve and RWAL modulator (valve in frame rail at rear), I had what I thought were pretty good brakes, but they just did not feel like "normal" brakes, just the best that I have had on this truck. Recently my power steering pump high pressure hose started leaking, so I decided to replace the leaking O-rings also. I had checked the vacuum and it was 16 inches hg at idle and it was 18 at WOT.

I found that Rock auto is now selling re-manufactured vacuum pods for the early Non-IC trucks and a considerably lower price than the 400 dollars apiece that Cummins wants, less than 300 for the pair. After doing this, I can only say...WOO HOO . They finally feel like normal power brakes. I have not had a chance to check the vacuum, so I will post when I do.

The conclusions that I have drawn are these:

1. While the vacuum was within the 8 to 25 inches hg that the FSM says, it obviously had some other problem, like volume of air moved or something.

2.These brakes need to have all the components to function well, read They are the most finicky brakes that I have ever dealt with in 35 years of wrenching.

3. At least once of 2 times that I replaced my rear main seal was not necessary, because that oil was leaking from the O-rings in the power steering-vacuum system and traveling down to drip off the bottom of the view plate at the engine transmission area.

Sorry for the long post, but I guess that I want you non ic guys to know that YES it is possible to have normal brakes on our trucks, it's just not that cheap Mark

 

mine feel fine...for now... i know im leaking something in one of the 6 lines?...next to the engine. Between trans lines, brake lines, ps lines...they are all coated and show no signs of leaking...!!! My hunt continues. Maybe i'll check those pods...

 

All I can say is "may the force be with you" ...Mark

 

I checked the vacuum with the new pods and it is giving me 23 inches hg at idle and at WOT. I am not quite sure what this means, other than I would have to think that the 8 to 25 range given in the FSM is dubious at best and was probably some engineer's best guess...Mark

 

my vac runs at 22 and I replaced EVERY single part ,and now my brakes are Orgasmic! I think the system has no room for a week link anywhere in it

 

Rebal- I want mine orgasmic too! I replaced my booster and mastercylinder last night! If I pump them once they are now holding tight now! Before last night they were not! We bled the lines for 25 minutes and two units of fluid soo I know they were bled correct! Do I now have this same vacume line leak???????????? What should I do now or what else do I need to begin to start replacing? I want these things right and I know too many people with these trucks who have good breaks! Thanks in advance for the help!

 

have you adjusted the rear brakes?

 

I certainly did, and I am also sure that so did Rebal and DHT. although I am not trying to answer for them. I just wanted to say that my problem got better by degrees, each thing that I did made them a little better, but I did not have normal feeling brakes until I replaced the pods and achieved more than 18mm hg. I agree that this system has to have everything within relatively narrow parameters. I am convinced that many of the brake problems discussed ad nauseum on this forum are , at least partially, due to low vacuum. It could be that as other components of the system wear out that it puts more "load" on the vacuum system....Mark

 

What is your vacuum reading?...Mark

 

how does one go about monitor vacuum at WOT like you mentioned? Just hook up the gauge and rev the engine or does it have to be done while driving? I have a mityvac should i plumb this into the cab to monitor while driving?

My brakes are a lot better than they were the day i got the truck but they are no where near as good as other trucks and cars that i have drove.

 

Yes, just pull the big vac line that connects into the booster and plumb the mity vac into it, Then start er up and open the throttle all the way. Mine no longer changes and has a steady reading...Mark

 

when I did mine I replaced the proportional valve and RWAL also Your booster has a check valve in it so if your building vac a idle it should hold .I assume when you bled the brakes you started with the RWAL first?
I kept fighting things till I just did new everything Drum,shoes. springs
the only things I left were the hoses and the calipers I changed the year before
if you changed the booster did you adjust the shaft ? also you said you pumped the pedal,was that to get your pedal up ? if it sits and you have to pump it to get high pedal you ether have rear shoes out of adjust ,or air in or getting in .Im not doubting you skills but are you sure you started bleeding at the right rear first? when everything is set right the brakes work real good.and i carry 2000 lbs on board all the time (110 gal tank 3 full tool boxes and a false floor with junk under it)also I installed the 3" shoes and 1 ton wheel cylinders in the rear .my first gen stops every bit as good as my 2001

 

If you want to monitor the vacuum while you drive or pump the brakes, you can disconnect the smaller line that goes from the check valve on the booster to the vacuum sensor/switch on the fender. Run a line to your mity vac and you can drive and monitor. Your brake warning lights will go on while the switch is disconnected...Mark

 

Glad you found the cure! Took me a minute to find this in my favorites. I haven't ordered from them and don't know if they're even still around, I've just had this for a long time. Scroll down to the bottom for the rebuild kit.

http://www.fixinrams.com/id14.html


On edit, here's the new link. It looks like the rebuild kits are still the same price.

http://www.fixinrams.com/

 

I believe that kit is for the intercooled trucks...Mark P.S. I will note and post the part numbers after the Suns game. Also, The A1Cardone remans are less than half the price.