M1008 Guru's -what's this for ???

[bandit4369]

New project, 86 M1008, 6.2, th400, 208, 60/14, It was rolled over on its roof, but only has 30,00 miles on it. While checking it out I came across this and am not sure of what it is or does. I'm sure some of our M1008 gurus can enlighten me. It's located on the back right side, just in front of the rear axle. The bracketry for it attaches to the right frame rail and the lever towards the rear attaches to a bracket on the rear end. The lines running into and out of it are brake lines.

 

[k20]

Its a height sensing valve, it changes the vehicles brake bias based on how much of a load it is carrying. Its on my truck, it was on a part burban I had. I think its just 3/4ton up, and then it was only after a certain year.

 

[thatK30guy]

Its a pretty common setup on the '81 and newer 3/4 and 1 tons. I'd toss it out as my '85 K30 has it disconnected.

You can either remove the vertical bar or disconnect the output line that goes into the valve and hook that line to the rubber line fitting at the bracket. Doing this cleans up the valve area under the frame.

 

[sled_dog]

Its a pretty common setup on the '81 and newer 3/4 and 1 tons. I'd toss it out as my '85 K30 has it disconnected.

The previous owner of my Burb bypassed it. Problem on that truck was the rears would lock up WAY before the fronts on a hard stop. Wasn't terrible, just something you had to remember when you stabbed the brake. Others have bypassed theirs and not had the same result either.

 

[bandit4369]

Thanks guys I appreciate the info. I figured it had something to do with the brakes, but wasn't sure exactly what. I knew some one here would have the answer. Thanks again