Rear Brake Cylinders

[claude brousson]

A few days ago someone wrote that they were going to replace their
middle wheel cylinder with a 1-1/8" cyl.as part of doing a complete
brake job. In my opinion that is going to make a more agressive braking
action on those wheels and be putting more heat into those drums than
necessary.I did this on the advice of others, and while it works OK, at
some point when I'm flushing my system or doing something to it, I'm
going back to a 1-1/16" dia. bore for the middle boggie.I will leave the
rear one the same as OEM at 15/16" which is just fine. I'm not saying
that the larger size won't work, just that I think one will have a more
evenly balanced system.

Claude in Victoria,BC.

 

[john wright]

As a side note there is a very good article in the July 1996 GMC
Motorhome Marketplace on upgrading of the Brake system for those of you
that still want to use the rear drum brakes. The idea of going to the
larger (1 1/8" cylinder on the front bogey is because it provides a
greater portion of the rear braking. The force of the braking pushes
down on the front axle and tends to lift the rear. So bigger is better.
As for heating up the drums, the GMC is noted for getting is brakes hot
if you not careful, but not in this case. One item that really makes a
difference is to have your vacuum booster sensitized. Bob Lamey does
this for about $185 exchange and you will really notice the difference.

J.R. Wright
GMC Greatlaker
77 Eleganza II
Michigan

>
> A few days ago someone wrote that they were going to replace their
> middle wheel cylinder with a 1-1/8" cyl.as part of doing a complete
> brake job. In my opinion that is going to make a more agressive braking
> action on those wheels and be putting more heat into those drums than
> necessary.I did this on the advice of others, and while it works OK, at
> some point when I'm flushing my system or doing something to it, I'm
> going back to a 1-1/16" dia. bore for the middle boggie.I will leave the
> rear one the same as OEM at 15/16" which is just fine. I'm not saying
> that the larger size won't work, just that I think one will have a more
> evenly balanced system.
>
> Claude in Victoria,BC.

 

[dave lowry]

Claude;

Oops! I meant to say 1 1/16".

It's comforting to know that there's folks out there who are willing to
keep others from making mistakes.

Thanks for paying attention.

___________
Dave (& Dege), '76 Royale /_][__] [_] | "SR JAMES"
Santa Barbara, CA *-0------OO--* (our hobby)