[Sparky McShakerton]

does anyone know for sure if the 80's diplomat proportioning valves are the same as the truck ones? they look real similar but i want to make sure.

 

[chrysler300le]

Those aren' really proportioning valves. They are really distribution block/brake warning switch. The brake proportioning is done with the master cylinder. So i say yea the truck block would work, but if your in doubt there is plenty of diplomats in the junk yard.

 

[Chump]

I would still try to find the correct valve as Chrysler has used metering, proportioning and combination valves. Here's a good article on them.
www.mpbrakes.com/mpfaqvalving.htm

 

[chrysler300le]

I believe all that is part of your MC. Was just looking over a mopar action article on the brake warning switch that many people call a proportioning valve. They show a cutaway view of one and its clearly a switch and there is no proportioning to it. Still i would get one from another diplomat.

 

[Chump]

Yes there is a switch and a piston that may be machined specially to restrict fluid flow, there may also be an addition of a spring of different tensions for different applications. On my truck the valve is called a combination valve in the FSM and it incorporates a hold off valve for the disk brake system. I use a special tool/clip on the hold off valve if I pressure bleed the system. This keeps the valve in the proper position during a brake bleed and NO red light on the dash when you are done.

 

[chrysler300le]

Ok thats different then what i seen and it clearly shows some metering with that combination valve compared to what i seen.

 

[Sparky McShakerton]

so i'd be better off finding one out of a truck then?

 

[MoparMurdoc]

I would say that it'd be best to get one out of a similar truck, because there are a lot of different designs, they changed em like every year. If you can't get a stock one, just get an aftermarket adjustable one from summitracing or something.

 

[chrysler300le]

Opps i thought you were trying to get a block from a truck to work on a diplomat. Not the other way around. I really wouldn't use the ajustable ones. I would use one off a same tonage truck close to your year.

 

[MoparMurdoc]

Why not an adjustable one? Think I paid more for the correct one for my pickup then an adjustable one woulda been, and now I need an adjustable one anyways because im gonna have huge dually drums in the back.

 

[chrysler300le]

cause there is metering and pressure and all that good stuff. Check out the link chump posted earlier.

 

[Sparky McShakerton]

i'm gonna try to salvage the one from my 80 ramcharger,hopefully i'll be able to remove the brake line fittings from it..