| Crusing in the Passing Lane Joined: Jun 2011 Posts: 5,096 | GM and someToyota trucks have a factory proportioning valve hooked to the rear suspension so when loaded, more rear pressure is applied. Adding one of these valves should be relatively easy. Observe how they are hooked up and then copy.
Ed
'37 GMC T-18 w/ DD 4-53T, RTO-610, 6231 aux., '95 GMC running gear, full disc brakes, power steering, 22.5 wheels and tires.
'47 GMC 1 ton w/ 302, NP-540, 4wd, full width Blazer front axle.
'54 GMC 630 w/ 503 gasser, 5 speed, ex fire truck, shortened WB 4', install 8' bed.
'55 GMC 370 w/270, 420 4 speed, grain, dump bed truck from ND. Works OK.
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