Posted by C. Garbee on Wednesday, July 17, 2002 at 3:09PM :
In Reply to: M37 24V vs 12V conversion questions... posted by AAA on Wednesday, July 17, 2002 at 11:38AM :
I converted my M37 over to 12 volts when I installed the Cummins 4BT instead of converting the engine to 24 to match the truck...
The wiring and circuit breakers will work fine in 12 volts.
I did end up installing a relay on the headlight circuit since I was tripping the circuit breaker when the trailer (M101) was attached and all the lights where on... I have Hella E-Code lights with H4 burners at 55/60 watts for headlights. The rest of the bulbs cross easily from 24 to 12 volts and I have a listing of them on my webpage. Jeff Smith at MV Parts has a cross reference page on his website.
I installed gauges and wiper motors that run on 12 volts that are available in 24 volt versions and would have replaced them even if I had kept the truck 24 volts considering the poor condition and utility of the original units.
Jump starting other vehicles (and the couple of jump starts I have received) have been easier since 12 volts is a bit more of a "universal" vehicle voltage in the US, but it has not been a factor at vehicle rallies where folks have trucks with 6, 12, and 24 volt systems.
24 volts will "jump" a less then perfect connection in the wiring better than 12 volts and almost all of the military accessories such as M151 heaters and MRE heaters are designed for 24 volts so some of them either have to be modified to work in a converted truck are work less effectively.
All in all I'm happy with my truck, but if I was to start over, I think that I would go with 24, although the little gremlins would likely still haunt me...
Check out my webpage for a bit more info, or send me an email.