86 GMC Sierra Classic Camper Special rear brakes?

[Duane T]

My GMC has what looks like a proportioning valve mounted above the rear axle on a cross member, there is a rod running from the top of the 3rd member to what looks like a control arm on this valve. the brake lines run into this "valve" first then from there to the axle. i have looked in several books and am not able to find any information on this valve. as a matter of fact i haven't been able to find much for information on the extras that were factory installed on this vehicle. i have contacted the manufacturer, but usually get a runaround. seems they don't like to tell you anything...lol. any help would be appreciated.

 

[Molson02536]

My GMC has what looks like a proportioning valve mounted above the rear axle on a cross member, there is a rod running from the top of the 3rd member to what looks like a control arm on this valve. the brake lines run into this "valve" first then from there to the axle. i have looked in several books and am not able to find any information on this valve. as a matter of fact i haven't been able to find much for information on the extras that were factory installed on this vehicle. i have contacted the manufacturer, but usually get a runaround. seems they don't like to tell you anything...lol. any help would be appreciated.

Here is a link that should help you get your answer. Good luck and feel free to ask us any questions.

http://www.compnine.com/index.php?r=1&makecode=L&year=1986