Generac GP5500 Portable Generator Review

Ian Mutuli
Updated on
Ian Mutuli

Ian Mutuli

Founder and Managing Editor of Archute. He is also a graduate architect from The University of Nairobi, Kenya.
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Generac was the first company to introduce a standby home generator. With over 50 years of glorious history, today it’s a name to reckon with.

In this generator review, we’ll have a look at Generac 5939 GP5500, one of the company’s flagship products.

Generac 5939 GP5500 is a powerful, long-lasting, and lightweight generator capable of delivering 6875 starting watts and 5500 running watts. This much power is enough to light up plenty of appliances including refrigerators, TVs, computers, etc.

It is one of the most reliable portable generators not only because it can be easily taken from place to place but for the clean electricity it produces. You can charge and run sensitive electronics without having to worry about anything,

Let’s dig in and find more about this portable generator:


Generac 389cc OHV

Start System

Manual recoil


(4) 5-20R 120V outlets and (1) L14-30R Twist-Lock 120/240V outlet





Fuel tank

7.2 gallons


180 pounds


28.8 x 26.8 x 25 inches


10 hours at 50% load


9.5” heavy duty wheels

Generac 5939 GP5500 Features:

Powerful Engine: Generac 389cc OHV is a solid engine capable of delivering consistent power. Splash lubrication makes it a long lasting engine which is a great plus. This unit can be used outdoors for camping trips or as a backup source.

Frame: The generator is enclosed in a durable frame made up of 1 ¼ hard steel tube cradle. It makes the unit durable and also safer to use.

Large Fuel Tank: The generator is equipped with a 7.5-gallon fuel tank that continues to deliver continuous power. There’s also a fuel gauge installed on the tank that allows you to check fuel level.

This makes it easier as you will never run out of oil since you’ll know when it’s time for a refill.

Low Oil Alert: The low-oil shutdown feature turns the engine off when there is little to no oil in the unit. This is of huge importance as a low level of oil can harm the engine and cause the unit to malfunction. This, however, is not a trouble with Generac 5939 GP5500.

Hour Meter: You can track maintenance intervals using the hour meter that comes equipped on the generator. This makes management easier and reduces the burden.

Runtime: This portable generator can run for up to 10 hours on a full tank at 50% load. Decreasing the load will increase the runtime by a few more hours.

Circuit Breaker: It’s a safety feature that protects outlets from getting damaged due to current overload. Thanks to it, the unit will automatically trip if it feels burdened.

This does not only keep the generator safe but also prevents appliances from sustaining damage.

Easier To Move: Do not let its weight of 180 pounds scare you, the generator comes with large tires underneath the body that make it easier to move the unit from one place to another. Its never-flat wheels are very durable and can bear the weight of the unit without any trouble.

Starting: This unit has a manual recoil start system that some users may not like. It can, in fact, take two tries to turn on the engine.

Outlets: The unit incorporates four 5-20R 120V outlets and one L14-30R Twist-Lock 120/240V outlet. Thanks to them, you can power up to 5 different appliances simultaneously.

Handle Style:  It comes with a fold and lock handle. It’s cleverly designed and puts no strain on the body.

Warranty: The unit comes with 2 years of warranty for residential users. Commercial users get 1-year of warranty or 1,000 hours, whatever comes first. However, customer service is not very good and service centers can be difficult to find.

You can use this link to locate a dealer.

Quiet Operation: There’s a low tone muffler device attached to the unit that suppresses the noise produced by the generator when it’s operational. Thanks to it, picnics, trips, and camping expeditions become fun and relaxing.

The unit won’t disturb your sleep if you keep it a few feet away from your room.


  • Comes with a detailed manual.
  • You will get the first engine oil with the unit.
  • Clean electricity production makes it safe to use.
  • Quite durable thanks to a strong frame
  • Circuit breaker prevents overloading.
  • Tracks usage between maintenance intervals.


  • Not CARB compliant, hence not for use in California
  • No parallel capability (connect two units to increase power).
  • The recoil system can be a bit hard to use

Generac 5939 GP5500 Portable Generator Review FAQS:

Q. Can I Use This Generator For Campings and Picnics?

Ans. You absolutely can. The unit is not very bulky and can easily be stored in a vehicle. Moreover, it contains 5 outlets which is pretty good. It may be a bit noisy but extensions will solve the problem.

Q. How durable is the unit?

Ans. While it is sturdy, some parts may break down or need repairs within a few years of use.

Q. Is the customer service bad?

Ans. Generac is known for quality products but a dealer can be hard to find in some regions.


Generac 5939 GP5500 is an excellent pick if you want power and portability. Its biggest downfall is a lack of electric start, poor customer service, and no parallel capability. Nonetheless, it works well for indoor and outdoor use as it is easy to use and quite powerful.

Ian Mutuli

About the author

Ian Mutuli

Founder and Managing Editor of Archute. He is also a graduate architect from The University of Nairobi, Kenya.
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