Farley`s Dodge Diplomat Forum

Forum Index => The Garage => Topic started by: Erics5th on December 05, 2009, 14:17:42

Title: Brake proportioning valve
Post by: Erics5th on December 05, 2009, 14:17:42
I was told the brake prop. valve is different on M police cars vs regular M bodies due to the 11" rear brakes. True?
Title: Re: Brake proportioning valve
Post by: DobaMark on December 05, 2009, 14:26:02
In the 1982 parts catalog, there are two listed, one for the cop cars, the other for the civilians.
In the 1989 parts catalog, only one is listed so it covers both applications,  Same part number as the 1982 non-cop one.

I swapped to 11" drums with the new rear axle on my 1982 New Yorker Fifth Avenue and never changed anything else.  It was fine except for the parking brake cables.
Title: Re: Brake proportioning valve
Post by: Mike on December 05, 2009, 16:30:15
1989 doesn't have 11" brakes that's probably why there's only 1.
Title: Re: Brake proportioning valve
Post by: DobaMark on December 05, 2009, 16:35:49
The 1989 parts catalog still shows an 11" rear brake available.  I know the 1989 cop car I parted out had 11" drums, same as the 1988 I had.
I did also look in the 1987 parts catalog, only one valve there too.
Title: Re: Brake proportioning valve
Post by: Mike on December 05, 2009, 16:51:42
Strange. The ones Ive grabbed parts from didn't have them and there have been people around here before who also had 1988 & 89s without it along with someone who dealt with them when they were new and said the same thing? Must be one of those oddball things.
Title: Re: Brake proportioning valve
Post by: Erics5th on December 06, 2009, 00:54:33
Thanks guys. Mark: What was different about the parking brake cables?
Title: Re: Brake proportioning valve
Post by: DobaMark on December 06, 2009, 05:31:51
The ones on my car were too short, the 11" drum uses a slightly longer parking brake cable.  According to the Raybestos parts listing, the difference is only 1/2".  I think some people have been able to make this work without swapping cables but I could not.
Title: Re: Brake proportioning valve
Post by: Mike on December 06, 2009, 13:32:27
That's strange. It should be the other way around. I know 11" cables are too short if you have 10" brakes and they should be 1/2" shorter since that's how much bigger the brakes are on each side.
Title: Re: Brake proportioning valve
Post by: lsm360 on December 06, 2009, 14:57:47
The ones on my car were too short, the 11" drum uses a slightly longer parking brake cable.  According to the Raybestos parts listing, the difference is only 1/2".  I think some people have been able to make this work without swapping cables but I could not.
I put an 8 1/4 with 11" into my previous 1985 non ahb, and parking brake cable was fine, as was the proportioning valve. I guess it just depends on the cars cables from the factory. Maybe some just had an extra 1/2" or so.
Larry
Title: Re: Brake proportioning valve
Post by: Erics5th on December 06, 2009, 23:16:33
I have an 8 3/4 from a '69 Plymouth Satellite on my '84 F/A, so this may be a concern for me...