Split brake system

[gimpyrobb]

Bear with me as this will be long winded. I started MVs with an M725. Alot of the guys on the 715 zone would use a corvette master cyl so they could "upgrade" to a dual circuit system. In a single circuit system, one part failure would result in no brakes. Same with a deuce. One of the guys put rockwell axles under his truck and was unhappy with his brakes. He did some looking and found a 2001 3500 master with hydro-boost worked out great. It has a 1 9/16ths bore. Anyone know what the bore is on a deuce master? Anyway, Could this dual circuit master be put on a deuce and have a second airpack added, so you could have a dual circuit system? I have looked around and not found much info on obtaining a dual circuit system that is made for the deuce.

 

[dm22630]

I have been wondering the same thing for 2 weeks now.....

I look forward to hear what you guys have done with yours. Also, what is needed to upgrade a deuce/5 ton to the dual braking system of a late model M35A2 (late 80's)?? They had much safer brakes right?

Thanks!

opcorn:

 

[russ81]

I have recently bobbed my deuce, and am looking at installing a break system that is completely hydraulic. I know that Ford uses wet breaks on their F-650's and half of the F-750's. The 850's are all strickly air. With all this in mind, considering the weight, towing capacity, and load capacity of a bobbed deuce, I don't see where there would be much difference between my truck and an F-650/750. So, all this ranting and raving brings me to the point that I'm trying to make. Why do you need the air assist? Isn't this just another system to break down. I know vaccum is an issue with diesels, but there are a lot of ways around that with today's technology.

 

[littlebob]

Don't know, just asking. What does the M35A3 use? I thought I read they had a dual circuit.
As far as the hydraulic boost, I've seen something on the site about someone putting a hydraulic pump on the front of the motor to run power steering, the same pump could power a brake booster.
littlebob

 

[SCSG-G4]

In the technical manual section, there is an entry called :
SMARPI 9-2320-209-14&P Split Air-Hydaulic Brake System (Modified M44A2 2-1/2 Ton Series Truck)even has illustrations on how the system was done (page 9)

 

[gimpyrobb]

Well, if you don't want to use air assist for the breaks, Tom(spicergear) put a hydro boost system on from a big truck and said it worked great, but he had to put a hanging pedal in to use it. A search should bring up the info. I was hopeing to just branch the single circuit into a dual circuit.

 

[gimpyrobb]

Thanks Mike, thats what I was wanting to make. I have not found the specific master that those systems use, so I was thinking of this other master to make the dual circuit.

 

[randyscycle]

If I remember correctly when I rebuilt my deuce master cylinder it was 1-3/4" diameter.

In theory a second airpack and all the necessary lines to make two independent systems should work just fine. Is there enough air in the tanks for reserve running two airpacks though? That'd be my biggest question.

 

[littlebob]

Thanks Mike too! I hope this is posted in the TM section too. I have already added it to my desktop Deuce folder.
littlebob

 

[DanMartin]

See this pic from the TM mentioned above. Note all the stuff with asterisks...that's all new stuff, plus all of the plumbing. It's all really tight in there too...just FYI.

 

[HeadWizard]

I have recently bobbed my deuce, and am looking at installing a break system that is completely hydraulic. I know that Ford uses wet breaks on their F-650's and half of the F-750's. The 850's are all strickly air. With all this in mind, considering the weight, towing capacity, and load capacity of a bobbed deuce, I don't see where there would be much difference between my truck and an F-650/750. So, all this ranting and raving brings me to the point that I'm trying to make. Why do you need the air assist? Isn't this just another system to break down. I know vaccum is an issue with diesels, but there are a lot of ways around that with today's technology.

Please keep us (me) informed as you move forward on your bobbed Deuces brakes. I don't know about the rest of those out there with bobbers, but with the much larger tires and one less braking axle, mine does not stop near as well as any of my regular deuces. I'd be happy to find a viable brake upgrade.

Don

 

[Recovry4x4]

Memphis Equip has the masters for the -A3. All you would need is the pedal assy as its much different. From there add a second air pack and do the plumbing. You will also need to abscond some type of proportioning valve. Side note, going to the -A3 stuff for this eliminates the spot that the PTO shifter bolts too so that would have to be re-engineered.

 

[Crazyguyla]

Side note, going to the -A3 stuff for this eliminates the spot that the PTO shifter bolts too so that would have to be re-engineered.

One could just engineer up a hydrolic winch setup like an A3 too what fun that would be.

 

[5tonpuller]

Memphis Equip has the masters for the -A3. All you would need is the pedal assy as its much different. From there add a second air pack and do the plumbing. You will also need to abscond some type of proportioning valve. Side note, going to the -A3 stuff for this eliminates the spot that the PTO shifter bolts too so that would have to be re-engineered.

Some place on the old sight, there is a thread about this too. I think there is even part numbers or a kit number for Memphis. ( of course I can not find it now )

 

[Warthog]

Hey Gimp,

I have a '87 M35A2C with the dual MC/Airpack setup. I can take pictures if you would like.

Warthog

 

[gimpyrobb]

Could you get a shot of the master and the second(pass side) airpack? That would be great.

 

[Warthog]

It will be tommorrow after the"snow showers" pass thru. I like ya but it's too cold outside (38 degrees, I know many others are colder...LOL).

Let me know if you want any other pics.

Warthog

 

[hndrsonj]

Kenny pretty much answered it all. Memphis has the master cylinders (around $250). Problem is they don't have the mounts which are totally different. They also don't have the proportioning valves. AM General is the maker of these parts and will not sell to the general public for liability reasons. I called and tried to order and have the parts sent to my work (US Navy) was a no go without a Govt credit card. Best bet would be to try and find a parts A3 and get parts that way. CSI in Talapoosa had one. I know that they were not sure they were going to try to fix so that may be an option.

 

[DanMartin]

Note to all that the A3 and the late model (late 80s) A2s have the same braking system (split system) with only minor tweaks.

Note also that the air tanks on the split system are different...two chamber air tanks.

Honestly, this is a complicated retro-fit. If it wasn't, it would be done more often by now. Even the depot rebuilt trucks kept the single system (unless rebuilt into an A3).

I would love to see someone do this swap....but please don't under-estimate how much work and parts it's really going to take.

 

[avengeusa]

there has to be a better mousetrap......

even a dual circuit master cylinder with front, and rear chambers would be great

gotta be a truck out there with something compatible....