Looking at the options on a new RV and the Onan QG 3600 LP is listed as standard and the QD 3200 (Diesel) is the option. I have not been able to pin down the cost, but it's got to be 3 or 4 thousand dollars more. The dealers are vague on the details. I currently have a QD 3200. I have read the pros and cons of each fuel and the overall cost of operation. In six years, it has only accumulated 185 hours. I have no idea how that compares to the average RV generator.Here is how I use it: When parked en-route, I will run the generator for the AC. Generally, there is always power at our destination. Noise restrictions limit the use just about everywhere. I have the RV generator and my house set up for emergency power and the only time I had it connected was to test the setup. Of course, the electricity has never gone out in the six years I have had this arrangement. Any other demand such as charging the batteries does not load the generator enough. Not sure if staying with Diesel is worth the extra initial cost. All I know that when we were stuck in a blizzard overnight, the Diesel started right up an kept us going. A friend had a LP generator and all I hear from him was how hard it was to start.

On board LP tanks can run out and diesel tanks can reach the 1/4 tank level shutting down the generator. That said it's easier to find diesel on the road, diesel can be added from containers at one's home in an emergency. Propane requires a trip to a bulk tank or a visit from a supplier if at home, if they will fill it, neither source is as readily available as diesel fuel.

Biggest plus for the diesel is amount of fuel needed to keep it running. They are very fuel efficient compared to a LP generator. With number of hours yours has run. It would not warrant switching to Diesel.

Teacher's Pet wrote:On board LP tanks can run out and diesel tanks can reach the 1/4 tank level shutting down the generator. That said it's easier to find diesel on the road, diesel can be added from containers at one's home in an emergency. Propane requires a trip to a bulk tank or a visit from a supplier if at home, if they will fill it, neither source is as readily available as diesel fuel.X2

Your diesel fuel tank is much larger than your LP tank, particularly when you take into account the fact that diesel provides a good bit more potential energy per unit volume than LP.For the amount you use the generator, I agree that the difference in initial cost would seem to make the LP generator the logical choice if you can manage with its fuel usage. It might also be sensible to instead carry a portable generator, though that's less convenient to use and yet another fuel to deal with.

Sounds like time for another dealer if they cannot provide you a price.

Diesel or LP generator | Good Sam Community

klutchdust
Explorer II
Sep 03, 2016
A lot of if's. Tornados, hurricanes, earthquakes. I have portable generators at home and keep the MH tank full before I park it in my secret location behind my house. With 55 gallons of gas i can run my

portables for quite some time. LP sounds the way to go, I have my LP piped for an external BBQ, I can use a 5 gallon LP and run my gen off of that If I cared too.
j-d
Explorer II
Sep 03, 2016
If I'm spending YOUR money, Diesel. And Diesel is a great fuel besides.

If I'm using the coach like you say you will and I'm spending MY money, it's LPG.

I wondered if the Diesel came with a weight penalty. It's 208-lb according to specs, and the LPG is 172-lb. 36-lb penalty doesn't seem like much. Also puts out 10% less wattage. Is that important to you?

We used a truck camper with a 2800 LPG generator. The TC did NOT have A/C (in Alaska we didn't need it...) but I can say it started and ran well for microwave, coffee maker etc.
loggenrock
Explorer
Sep 03, 2016
185 hours isn't very much. If you look at the VAST majority of emergency generators at municipal buildings, etc., they are propane. Why? Propane doesn't go bad sitting in a tank. No algae, won't gel in the cold, etc. What size propane tank in the potential new rig? That's one of the reasons I opted for the Prism - it has an 80# on board LPG tank. That's almost 15 gallons of usable propane. At 6/10 gallon per hour at 1/2 load, that's 25 hours run time on a full tank. If you're worried about refilling it, just add an Extend-a-stay, then you can connect another tank, be it a 20# or a 100#er. Propane vaporizes to -40 degrees, gasoline to -73, diesel will gel at about +10 degrees. ST
Community Alumni
Sep 03, 2016
The Diesel option will cost $$3,540 more. I have weighed the pros and cons and I think I will opt for the LP generator. I don't think I put enough hours on our QD 3200 to stick with it. There are times when I could do without the soot; too bad it isn't as clean as the exhaust from the MB engine up front. The generator quitting when there is at least 18 hours of Diesel in the tank is annoying. I keep the RV at home and I installed a 30 Amp outlet for it. I have a set-up for powering the house if necessary and the LP generator will work as well. I will have to work out the fuel thing for extended times. I know a lot of people that have installed stationary gen-sets (natural gas) and have yet to get a return on their investment. However, if I stored the RV away from home, I would get a properly sized portable generator. As I said before, the more prepared you are, the less likely bad stuff happens.
AJR
Explorer
Sep 04, 2016
Your big tank will be diesel. So go with it.
Toot_Mc
Explorer
Sep 04, 2016
Had a Propane gen set on my diesel pusher when I bought it. Changed it to Diesel as soon as I could. Propane was hard to find on road in small towns. Running Gen set all day when traveling had to fill 37 gallon tank every other day. and propane was expensive. used more than a gallon of propane per hour for a 6.5 kw. generator. I found diesel generator with Catapiller (perkins) 3 cylinder engine 8 kw and installed it myself replacing 6.5 kw get set.

best swap out i ever did. Never had to find fuel again. Never had to wait for stations in small towns to find guy who was qualified to operate the Propane equipment to fill my Motorhome every other day again. My propane in motorhome would last for weeks just running Refrig. and heater in winter.

Would never recommend another propane generator to any one again.....!!!!!!!!

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