But have no Idea what to search under?
There is an arm going from the brake block to my rear axle. Its like a 1/4" round tube on a linkage from a location between the pumpkin and the drivers side wheel to a brake block (per-portioning valve?) on the frame. Whats it for, do i need it?
Does it apply brakes in the event that the axle comes too far out of line with the frame or something?

Im sure its been asked but like I say, I dont know what to look under?

 

Are you taking about the LSPV sensor arm? It prevents the rear brakes from locking up if you're not hauling anything, and if you are the rear end sitting lower pushes on the LSPV and applies the rear brakes more.

 

I can see what your saying, sounds completely logical. I will do a search on LSVP arm then thank you.
Ive got one inch longer rear greasable shackles on my truck, how has that effected my rear braking?

 

Normally that would mean the truck doesn't apply the rear brakes as much, but it may have been adjusted already.

BTW, that box is called the "Load Sensing Proportioning Valve / Bypass Valve" to help with your searches.

 

Thank you
I installed the shackles so It was likely never adjusted. LOL
Can I Bypass it, (mount it in one position and forget it?) or is it important on these little trucks?
I pull a small trailer from time to time but dont really do big loads.

 

Some people install a manual proportioning valve, but if it's working I wouldn't mess with it. You certainly can't just bypass it, as your rear brakes will lock up long before the fronts begin to slow down the vehicle. Or on the other hand if you don't have any rear braking force when towing (even a small trailer) the truck will try to jackknife on you.

The LSP/BV was essential on trucks in the days before ABS came standard, you've got to adapt to changing cargo loads.

 

Ok, Thanks

 

I have mine set to one position and haven't had any issues with it but I don't tow or haul heavy loads in the bed. It took me a few tires to get it set right to not lock up the rear brakes in a panic stop but it works for me.

 

Im thinking along the same line as you. I just checked mine and although I have a shackle lift the arm seems to be almost bottomed out as if it were sensing a loaded bed. Im guessing the rod has been previously bent or miss shapen . I found an article in my searches that will allow me to disconnect it and fabricate an adjustable linkage using a turnbuckle mounted to a stationary location or similar. In my area abs systems are frowned on and ive hit a deer because of them in the past so ill probably set it up to adjust manually.