Fuel Per Hour: How Much Gas Does an Onan 5500 Generator Use?

When you use your generator, you do need to have some fuel on hand. Once you figure out how many gallons your generator burns per hour it is easy to know when you have to get more fuel. Some people use their generators all the time.

The Onan 5500 is rated at using .6 to .7 gallons per hour. After 10 hours you should have used between 6 and 7 gallons of fuel. But this result is the idea and results vary for elevation and weather plus load requirements.

To learn more about this important topic, just continue to read our article. It has the information you want to know about so you can plan on how much fuel you need on hand and when to get more. It s not a challenging task but a vital one.

How Much Gas Does an Onan 5500-Watt Generator Use?


It is said that it does not matter the model number and that basically all gas, not LP, generators use the same amount of fuel per hour. That is as reported between .6 and .7 gallons per hour.

As we also mentioned already, your results will depend on where you are camping and the weather. Altitude does affect the Onan’s performance and the higher you go you may lose performance and have more fuel consumption.

How long you get generator power and before you need to refuel depends on the size of the fuel tank. Some people may exaggerate their results some. There is always one person in the crowd that needs to be #1 and may overstate his results.

Over the course of your camping and generator use, you should expect to get about .6 gallons of use per hour. That is the most commonly reported result and that is the figure on the spec sheet.

Onan Marquis Gold 5500 Fuel Consumption


There are 3 numbers associated with this tat for this generator. With no load, you can expect the Marquis to use about .3 gallons per hour. We are talking about the 5500W model and not the 7000W model.

When you are using a half load, then you can expect to use about .6 gallons per hour. Then for a full load, you will burn roughly .9 gallons per hour. So in a 10-hour day of use, you can expect to burn 9 gallons on a full load.

That will be 6 gallons on 1/2 load and 3 gallons on no load. Those figures are just a reference guide as your results will vary depending on temperature and altitude.

When you need to refill the fuel tank will depend on your usage. As you know the more you use your generator, the more often you have to buy fuel. Plan your use well so you are not driving long distances to get more fuel.

How Much Propane Does an Onan 5500 Use?


On the Marquis 5500W spec sheet, there are again 3 numbers to think about. These numbers should be the same for the other 5500W models as the gas figures are for all 5500W models.

At no load, the generator will use only .4 gallons, and we should mention that these figures for LP and gas are at 60 Hz. The 1/2 load fuel use is at .8 gallons and finally, the full load is rated at 1.1 gallons.

As you can see, you will burn your propane a lot faster than you will regular gas. We do not see buying the propane model option as being more efficient than the gas version.

We have not checked the price yet so you may recoup some savings if the propane is cheaper to buy than the gas option.

Onan 5500 LP Generator Fuel Consumption


You should find that the other LP 5500W Onan generators will run at the same levels as the Marquis model. These use about .8 gallons of propane per hour at 1/2 load. For the other load levels just check the previous section.

We did find out that the cost of the gas and the LP generator models is roughly the same. They will set you back about $4000 depending on where you buy your generators.

If you go cheap and buy a lesser model, you may save on the purchase price but will lose money in the long run. Those lower models may be cheaper but they also use a lot more fuel. The choice will be yours, of course.

How Long Will an Onan 5500 Generator Run On a Gallon Of Gas?


This will depend on several factors. You may not get the best performance when it is a hot day outside or you are camping high in the mountains. The ideal spot is closer to sea level and on warm but not hot days.

Given the figures on the spec sheets, you can expect to use about 6 gallons of gas over 10 hours of use. For LP, you can expect to use about 8 gallons of propane.

If you opt for the diesel model, then expect to use about 4.5 to 4.9 gallons of diesel fuel over 10 hours. Then the per gallon use will change depending on which Onan generator model you buy. The 5500ws are all the same but the 4000W will get about .5 gallons per hour.

Figure out how much power you need and go with the best generator for your needs.

Some Final Words

Onan generators are supposed to be very fuel efficient. If you do not need a lot of appliances or other electrical devices running at the same time, you can expect the tank of gas to last you a long time.

Do your comparison shopping and see if the 5500 or the Marquis will best suit your camping needs. They should run about the same price and with the same fuel consumption, it is a matter of preference.

This should help you plan your fuel runs and make sure you spend more time relaxing than driving for fuel.

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