Generac GP Series Portable Generators: Because One Size Does Not Fit All

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The Generac GP series of portable generators spans a wide range of power levels. There are over 10 models (depending on how you count) in this line, with the largest model giving you over 10 times the power of the smallest.

In this review, I’ll concentrate mostly on the six small to medium sized models, generators that you would most likely want at home, at the park, or out in the woods.

If you are in a rush and just want to check the pricing and availability of these Generac GP generators at Amazon, you can click (tap) a link in this list below. (You may have to scroll down a little on some of the Amazon pages to find the generator itself.)

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How Do the Generac GP Generators Compare to Each Other?

In general, as you move up the line in this GP series, the main benefit you get is more power. Along the way, you get a new feature or two from one step to the next. There are a few quirks in this path that I’ll explain as we go.

I’ve divided the ten generators in the list above into three groups, partly so I could present their specifications more easily in the tables that you’ll see below.

You will generally be able to tell, by glancing at the model number, how much power a given machine provides, as well as its starting mechanism (“E” for electric start) and whether or not it uses inverter technology (“i” for inverter).

Here them are the first three lowest power models in the GP series.

Model GP1800 GP2200i GP3250
Running Watts 1800 1700 3250
Starting Watts 2050 2200 3750
AC Voltage 120 120 120 / 240
AC Frequency (Hz) 60 60 60
Engine Displacement (cc) 163 80 208
Engine Type OHV OHV OHV
Lubrication Method Splash Splash Splash
Automatic Voltage Regulation? Yes n/a n/a
Starter Recoil Recoil Recoil
Low Oil Shutdown? Yes Yes Yes
Fuel Gauge? Yes n/a Yes
Fuel Tank Capacity (gal.) 3.5 1.2 3.5
Run Time (hrs.) 10.5 @ 50% 10.75 @ 25% 9.7 @ 50%
Warranty 2 yr. limited residential;
1 yr. limited commercial
2 yr. limited residential;
1 yr. limited commercial
2 yr. limited residential;
1 yr. limited commercial
Dimensions LxWxH (in.) 22.75 x 16.75 x 17.25 19.7 x 11.4 x 17.9 22.75 x 22 x 21
Weight (lbs.) 84 46.6 110


Generac GP1800


Despite being the first in the list, the GP1800 is not the smallest generator in the GP series. That designation goes to the GP2200i. (More on that below.)

The only other notable feature not mentioned in the table above is that the GP1800 is legal to use in 49 states (not California) and in Canada.

As is common on smaller generators, you get just two 120 volt receptacles as shown above (even though the text says there’s only one).

Generac GP2200i


The GP2200i is Generac’s only machine in this series that uses inverter technology. This makes it quieter than most and allows you to run more sensitive electronics (computers, etc.) with relative safety.

Being an inverter is also apparently Generac’s excuse for messing up the ability to compare this model on equal ground with other GP series generators.

Despite being labeled a 2200 watt generator (in the model number), you’ll note that this model really only gives you 1700 running watts, making it the smallest of the GP machines.

On top of that, Generac only gives a run time rating at 25% load, instead of the 50% given for all other GP models. Of course, this makes it look, at first glance, like the GP2200i is on par with the GP1800 and the GP3250. But 10.75 hours at 25% probably equates to something closer to 4 or 5 hours at 50% load.

In the diagram above, I think there is another error. You actually get 2 receptacles in the lower right portion of the panel. Perhaps they mean there is one area of the panel for these two outlets…?

You can also see there is a USB outlet for those sensitive electronics and parallel outlets for chaining generators together when you need additional power.

The fuel economy switch is one of those items that I wonder why you would ever set to the “off” position – or why they even include it at all, instead of permanently giving you better fuel economy.

The GP2200i is legal in all 50 states and Canada.

Generac GP3250


The GP3250 is the first in the line to sport wheels and a folding handle. You get heavy-duty, never-flat, solid, 8 inch wheels so you can push or pull its 110 pounds around more easily.

Again, you get 2 receptacle in the one area. At this power and price point, you also get a twist-lock 120 / 240 volt outlet.

The GP3250 is legal in just 49 states and Canada, like the GP1800.

Next we come to the midrange models which are very similar to each other.

Model GP5500 GP6500 GP6500E
Running Watts 5500 6500 6500
Starting Watts 6875 8125 8125
AC Voltage 120 / 240 120 / 240 120 / 240
AC Frequency (Hz) 60 60 60
Engine Displacement (cc) 389 389 389
Engine Type OHV OHV OHV
Lubrication Method Splash Splash Splash
Automatic Voltage Regulation? Yes Yes Yes
Starter Recoil Recoil Electric / Recoil
Low Oil Shutdown? Yes Yes Yes
Fuel Gauge? Yes Yes Yes
Fuel Tank Capacity (gal.) 7.2 7.2 7.2
Run Time (hrs.) 10 @ 50% 10 @ 50% 10 @ 50%
Warranty 2 yrs. limited residential;
1 yr. limited commercial
2 yrs. limited residential;
1 yr. limited commercial
2 yrs. limited residential;
1 yr. limited commercial
Dimensions LxWxH (in.) 27.25 x 27 x 25 27.25 x 27 x 25 27.25 x 27 x 25
Weight (lbs.) 171 175 186


Generac GP5500, GP6500, and GP6500E


As you’ve seen in the table, these three models are virtually identical. The GP6500 simply gives you more power than the GP5500, and the GP6500E adds a battery for its electric starter.


All three have a fold-down, locking handle and heavy-duty, never-flat, solid, 9.5 inch wheels.

They also have an Hour Meter that helps you track maintenance intervals. Proper maintenance is especially important during your “off season”, because you need it to be ready to go when it’s “in season”. The GP6500E even includes a plug-in battery charger jack so you can keep that battery charged and ready for use.

The panel above is on the GP6500E, but is virtually identical (except for the electric start switch and battery charger) to that found on the other two models in this group.

You get two areas of 120 volt receptacles for a total of 4 outlets.

Both the GP5500 and the GP6500 come in 3 flavors that allow you to use them either just in the 49 states, in the 49 states and Canada, or in all 50 states and Canada. Be sure to get the sub-model that fits your situation.

Generac GP7500E, GP8000E, GP15000E, and GP17500E

Finally, we get to the big boys. I didn’t make a table for them for reasons explained below.

The next two models up the line are really just large, more powerful versions of the GP6500E. Both the GP7500E and the GP8000E have electric starters with recoil backup, as the model name suggests.


The GP7500E has 9375 starting watts and can run about 11 hours at 50% load. The GP8000E has 10,000 starting watts and run for about 9.5 hours at 50%.

All of the engines discussed to this point are made overseas, presumably in China but I don’t know that for a fact. The final two industrial strength generators are made near Waukesha, Wisconsin, USA.

The GP15000E and GP17500E are intended for jobsite or other power-hungry areas. They have pneumatic wheels and a built-in eye on top that can be hooked to a crane for transport or storage.

The GP1500E gives you 22,500 starting watts, and the GP17500E gives 26,250 starting watts.


All the generators above are 60 Hertz models. Generac also makes three 50 Hertz models that I’ll just mention briefly here by model number in case you need such a machine. They are the GP2600, the GP5000, and the GP6000E.

Conclusions about the Generac GP Series Generators

While many owners are satisfied with their Generac GP purchases, some models seem to have more problems than others.

The best machines appear to be the GP2200i, GP6500, GP6500E, GP7500E, and the GP8000E (as well as the industrial models).

Problems that the others have include broken parts, bad carburetors, and just giving up the ghost after a relatively short period of use.

I would therefore have no qualms about recommending the better models that I just mentioned above, but I would probably stay away from the others and opt for a different manufacturer’s offerings (perhaps Honda) instead.

See the Generac GP6500E portable generator at Amazon now.

Gary Sonnenberg