Question: I work for a fire department and have recently been given custody of an '86 Chevrolet 1 1/4-ton truck from military surplus. I have been instructed to make it a forestry unit, but I have very little information on this truck since we just received it a few days ago. My chief is dead-set on converting it to a 12-volt system (more specifically, having me convert it). As I understand, all the normally replaced parts such as light bulbs are 12-volt, and the only part that I can find that is 24-volt is the starter ( which is working fine for now). What is the advantage of converting the entire system to 12 volts? Why would it be so bad to leave it alone until the starter dies and then convert the system as opposed to throwing away a perfectly good starter just because of the voltage it requires? Thanks and keep up the good work.
Justin, via 4wor.com
Answer: I have the exact same truck as what you are starting with, and so far I have not changed the system to 12 volts. Like yours, my truck uses two alternators and two batteries to supply 24 volts to run the starter, and then uses resistors to get 12 volts for everything else. I see you having two options, leaving the starter 24 volts and having a very strong starter to turn over the high-compression diesel engine, or changing it to a 12-volt starting system so you can get a cheap 12-volt GM diesel starter at just about any auto parts store in America. I chose the former until my starter dies (and because I'm too busy to do the swap), but even then I'll probably either get it rebuilt or get a rebuilt version from Boyce Equipment (800.748.4269). The 24-volt starter costs more than $200 and the 12-volt version costs between $85 and $185 depending on where you get it.
Another problem you might run into is that your truck has two alternators and two batteries run in series, and this results in more possible parts needing to be repaired or replaced down the road. I'm sure your chief is considering these costs in having you do the conversion, but if the truck is running fine, I would leave it alone for now. The higher-voltage starter should produce more torque for starting the truck and that alone is important if you are out fighting fires and need to get the truck moving in a hurry. I have found that there are more problems with the glow-plugs system than with the starter on my truck and modifying the glow-plug system with a manual temporary switch will probably be the best bet for you. If you do convert it to 12 volts you may find that the 12-volt starter is lacking in torque, in which case you might want to consider upgrading to a gear-reduction starter such as those made by Powermaster (865.688.5953) for the GM 6.5L or 6.2L diesel. However, the price of these is more comparable to a 24-volt military starter. There are awesome conversion instructions on the Internet at: www.roscommonequipmentcenter.com/news_notes/nn10.pdf. It shows the step-by-step instructions for converting from 24 volts to 12 volts. Another great military-vehicle Web site is www.steelsoldiers.com.
I think it's a great job you are doing there and I hope this was helpful in figuring out your next step with this truck. Since you'll be using this truck for firefighting, and hopefully protecting some off-road trails, I'd like to award you with this month's Tech Letter of the Month. I know your question is a bit more specific than what I would usually pick for this reward, but I think you'll be needing the Patriot 9500 UT winch from Ramsey Ramsey Winch (918.438.2760, www.ramseywinch.com) that I'll be sending you. It features a semiautomatic clutch that is faster than conventional self-recovery winches, and when used in conjunction with the Ramsey Patented Wireless Remote you will have near unstoppable power. The semiautomatic clutch reduces winching steps and saves operator time, and a sealed motor, drum, and gear carrier assembly protects the winch from the elements.
Question: I have an '01 Nissan Frontier and would like to make a few exterior/body modifications to my truck (things like fender flares, bars, lights, and so on), but I have yet to find a suitable Web site to find such parts for my truck. Are there any Web sites dedicated to off-roading Nissans or any place I can find quality Frontier body parts?
Lane, via 4wor.com
Answer: Performance Products (www.performanceproducts.com) offers a lot of Nissan accessories, and Nissan 4 Wheelers (www.nissan4wheelers.com) has an online Nissan community.