View attachment 227945 My manual shows 3/8" air line for the TC valve which seems fine, But you'd think the PP-7 valve would need a larger line. The air supply for the trailer has to come all the way from the tank, up into the cab through the valve and then back out to the TP valve and then to the trailer?
Glad to see you are fixing that correctly. Not many people are able to do what you are doing. Looks good.I installed a new 1/2 inch npt brass nipple, 1/2 x 3/8 adaptor and tied the drive axle service brake signal line into the primary delivery port on the foot valve.
After;
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