There should be no air leakage while the system is airing up , and if the leak is in the air suspension the tanks should still build to 65 PSI , That's enough to release the park brake .
Contact " Spartan Motor Home Support " ( they don't charge for info ) with your chassis serial number and ask for an air system diagram . They will be able to answer your other questions on , air dryer and governor locations .
99DSDP 3884, Freightliner, XC, CAT 3126B, 300 HP /ALLISON 3060
2000 Caravan toad, Remco & Blue Ox.