Truck has 24K miles, and I'm on my second lift pump, installed last summer. This one's a bit weird -- I'm wondering if they've changed the design, or ?

idle -- 16 psi

-anything- above idle -- 12 psi

WOT -- 12 psi

WOT uphill, pulling a load, 85*F ambient, 1250*F EGT -- 12 psi

Rock steady, never changes, pulling loads, cruising, lugging, getting on the pedal. Not the gauge, checked it with another.

Got -6AN fittings, lines from the LP to the VP, don't think that means anything, though.

 

Those are unusual readings, Tartarus. If they are accurate, you're pretty lucky! I haven't heard or read of any major changes in LP design. Is the pump you put in a Cummins pump?

DeWain

 

It's a warranty replacement from a DC dealer. Looks identical to the OE. Can't figure out how it could respond so quickly to throttle changes (inside the limits of the gauges); thought it might have a new internal regulator or check ball design.