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Your replacement pump motor is internally grounded, as opposed to the external ground on the original.
Look for a place ( threaded hole ) on the new manifold to attach the existing ground cable, and everything should work properly.
99DSDP 3884, Freightliner, XC, CAT 3126B, 300 HP /ALLISON 3060
2000 Caravan toad, Remco & Blue Ox.