spring brake conversion should i

4106-123 · November 20, 2007, 05:24:02 PM

should i change my rear brakes over to spring brakes, i have single chambers now and the icc valve with the johnson bar. i want to do what is safest and best. 1961 4106. has any one done this change pros and cons thanks in advance. george

lyndon · November 20, 2007, 05:58:44 PM

George, were you thinking having this done by a shop or as a DIY project? (Cost vs. a lot of plumbing, I would expect.)

Don

4106-123 · November 20, 2007, 06:04:11 PM

i was going to do it myself

Tom Y · November 20, 2007, 06:11:56 PM

I have a MCI 5C and spring brakes will NOT fit. The chambers are to big, I was looking at 30/30 spring brakes. Tom Y

4106-123 · November 20, 2007, 06:17:34 PM

from what i have read they use 30\30 chambers called mini max, the mounts have to be relocated also on the 4106

baker4106 · November 20, 2007, 06:25:18 PM

I have spring brakes on my 1961 4106 but they were on when i purchased it from Alan Baker. They work good and will slide the tires. Larry

Utahclaimjumper · November 21, 2007, 03:44:43 AM

I have the double chambered spring brake on my 62-06, required a 2.5 inch offset slack adjuster which is commonly available at most truck brake stores.>>>Dan

4106-123 · November 21, 2007, 06:05:00 AM

did you have to relocate the mounts or just use the offset slack adjuster?

Utahclaimjumper · November 21, 2007, 07:42:18 AM

I cut the slacks in half and offset them myself, then adjusted the actuator rods to the right length, works great.>>>Dan

lloyd · November 21, 2007, 07:53:48 AM

Has anyone tried installing 24/24 on a MCI 5A? I would like to install spring brakes instead of the DD3.

4106-123 · November 21, 2007, 09:13:49 AM

dan can you give me more info on what you mean that you cut the slacks in half? i want to do this swap and trying to get as much info as i can.i read in previous post that the chamber mounts had to be relocated. what chambers did you use?part numbers? thanks george

RJ · November 21, 2007, 09:20:13 AM

George -

Tom Caffery has done this swap on his 4106, I'm sure he will chime in here when he sees the thread.

But, for standard, off-the-shelf truck spring brakes to be installed, you have to cut off and reposition the brake can mounting points.

Can you weld?

If not, you're going to have trouble finding a welding shop that will do the work - liability reasons, mostly.

OTOH, if you're not to far from Chaz, I'm sure he can take care of you, and you'd get to visit with another busnut in the process. . .

FWIW & HTH. . .

Chaz · November 21, 2007, 09:34:10 AM

Well, I can't say as I have ANY idea of what a spring brake is or what to do.

I'd be glad to help if I can, but I'd have to know what the situation is.
Is the parent material mild steel, cast, spring steel, etc? Is it a small part that needs to be TIG-ed or would a MIG or arc welder do?
Keep me in the loop if you want.

Chaz

p.s. George, ya ought to put your town (or even are of the country) in your personal info. It kinda helps at times.

kyle4501 · November 21, 2007, 10:07:29 AM

Quote from: lloyd on November 21, 2007, 07:53:48 AM
Has anyone tried installing 24/24 on a MCI 5A? I would like to install spring brakes instead of the DD3.

The number indicates size of the brake chamber in square inches of surface area the air pressure acts on. As a result, the higher the number, the higher force applied to the brakes for a given application pressure.

If you replaced 30's with 24's, you would be reducing your braking ability by 20%.

There are worse things in life than DD3's.

4106-123 · November 21, 2007, 02:54:21 PM

my bus does not have the dd3 chambers they are single chambers. i think later year models went to the dd3s