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Freightliner didn't supply the genset with the bare chassis , the coach builder added it , so the mounting; solid or on a slide ; was up to the coach builder .
Can you get under the front of the coach to see if there is a rail system with roller bearings between the gen set and the frame ?
99DSDP 3884, Freightliner, XC, CAT 3126B, 300 HP /ALLISON 3060
2000 Caravan toad, Remco & Blue Ox.