Calfee’s Custom GMC Motorhome

The Calfee road show vehicle is a 1975 GMC Transmode. These are more commonly known as a GMC Motorhome but this one was originally a Transmode, which was their utility version.

These GMC Motorhomes are famous for their advanced design featuring: 

  • Front wheel drive powered by a 455 cubic inch Oldsmobile engine (Toronado)
  • Tandem rear wheels with air ride height adjustment
  • Aircraft aluminum frame construction with fiberglass fore and aft moldings

These features made it lightweight and with a low floor for easier step up and better aerodynamics.
The modifications we did are:

  • Removed the old roof AC and Onan generator – replaced with a mini split heat pump in the generator bay.
  • Added 1,500 watts of solar panels installed flat on the roof, charging 11kWh of Zero’s Lithium Ion Motorcycle batteries at 112V.
  • Solar panels are supported by two 16 foot long PVC pipes that hold 20 gallons of water that can be pressurized by the on board compressor.
  • Added a 24V system for the compressor, Unique Refrigerator and water pump.
  • Replaced cab ventilation routing and built a new dashboard.
  • Built out interior with mostly bamboo Plyboo materials and whole bamboo.
  • Added a wet bath with a composting toilet-in-a-drawer using those heavy duty drawer slides from the old generator.
  • Installed a ramp on the rear for transporting bicycles to expos – as well as motorcycles and other electric vehicles – that can be charged up on the big house batteries.
  • Installed a high quality sound system with a big subwoofer.