Viair 400p Vs. Smittybilt 2781

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If you opt for a piece of equipment that can help you with your professional or personal air needs, then it would be great to invest in a compressor.

Air compressors are perfect for filling your tires, powering HVAC systems, filling gas cylinders, and many more applications.

There are various manufacturers on the market, but there are two names that stand out the most – Viair and Smittybilt.

They offer various compressors, and it may be overwhelming to choose one that meets your needs and preferences.

In this guide, we’ll look at the difference between Viair 400P vs. Smittybilt 2781.

These units are two of the finest compressors of each brand. Keep on reading to find out more about them!

Viair 400P Air Compressor

Viair 400P Air Compressor

Viair 400P is a portable air compressor that is popular among off-road enthusiasts around the world.

This equipment is large yet very lightweight, weighing only 8.5 pounds. For sure, this ensures ease of maneuverability wherever you need it.

Moreover, it is a powerful device that comes with a maximum pressure of 150 PSI, thereby easier for you to inflate a large 35-inch tire from 0 to 30 PSI for as quickly as 6 minutes.

This unit also has a 5-in-1 deflator/inflator that allows you to save time and effort.

It can be done by intermittently providing air up and down and letting you check the tire pressure instantly.

As for the power of this unit, you’ll need to have a direct connection to the battery through the use of alligator clips that come in the package.

You should make sure to keep the engine of your car running while using this compressor to guarantee that you’ll meet the current and voltage requirements that you need.

What’s more amazing is that this unit can continuously work for about 15 minutes, but it requires a cool-off time of 30 minutes afterward.

It is also capable of shutting itself off by the time that it detects that it becomes too hot. This feature will allow you to avoid overheating for sure.

Many have been complaining about the length of the power cord since it only measures 8 feet.

This can practically lessen its ease of use and maneuverability. Although it has a 25 feet coiled air hose, this unit will still require you to use a jumper cable set to work around your vehicle and in hard to reach tires.

With these exceptional features and attributes, you’re to have a piece of equipment that can deliver both performance and quality without any disappointment.


  • A reliable and portable compressor
  • Includes a diamond-plate sand tray to keep it stable
  • Equipped with a heavy-duty pump
  • Has a thermal overload protection
  • Comes with dual battery clamps and 3 inflation tips


  • It tends to be very hot when used for a long time

Latest Comparison: Viair 300P Vs. 400P

Smittybilt 2781 Air Compressor

Smittybilt 2781 Air Compressor

Smittybilt 2781 is the best option to choose if you need an air compressor for various automotive applications.

It is known to be the most powerful in its class in a way that it is driven by a ⅓ horsepower oil-less direct-drive motor.

You’ll be impressed with the maximum airflow of this equipment which has a rate of about 5.65 CFM or 160 LPM.

This range is much better as compared to its competitors and the previous model from Smittybilt (2780) which has a rate of 2.54 CFM or 72 LPM.

Much more, the operating temperature of this model is from -4 deg F up to 140 deg F.

A lot of consumers commended its equipped automatic protection device. This feature will help you prevent any damage to the compressor in case it reaches an unsafe temperature.

In addition to that, by the time it reaches beyond the maximum operating temperature, the protection circuit that comes with it will immediately disconnect your equipment from the power source.

And when it goes back to the safe level, it automatically resets itself to go back to operation.

The unit also incorporates a 150 PSI pressure gauge located on the tire inflator. You won’t have any hard time in reading and checking the pressure of your tire.

Also, it has a convenient fast-release coil hose that measures 24 ft long. It’s a great length allowing you to access hard to reach tires, such as the trailer tires.

All in all, this product is jam-packed with numerous attributes and specifications that are price-worthy indeed.


  • Equipped with an auto-thermal cutoff switch
  • Lightweight yet powerful
  • Includes an E-Z twist inflator fabricated from brass
  • Has a 24 ft long coil hose and an easy-to-read pressure gauge


  • The pressure gauge has been giving inaccurate readings

Related Guide: Viair 88P and 300P air compressor comparison

Viair 400P Vs. Smittybilt 2781 Comparison

You may still find it hard to decide which one to buy between the two since it is somehow similar in some aspects.

But if you dig deeper about them, you’ll see some notable differences between them.

At this point in the article, we will be showing you a list of features that set them apart from each other. So, keep on reading!


One of the very first things that you will notice when you put the Viair 400P and Smittybilt 2781 side by side is their difference in built appearance. This factor will also affect both of their overall weight.

Viair 400P has dimensions measuring 11.25 x4 x7 inches and weight of 15 pounds, while the Smittybilt 2781 measures 16.1 x10.8 x11.4 inches and weight of 20 pounds.

Obviously, the Smittybilt 2781 is much larger and bulkier compared to the Viair 400P.

Air Flow

They also have different ratings when it comes to their airflow. The ratings are usually measured in CFM (cubic feet per minute) or LPM (liters per minute).

Viair 400P has an airflow of about 2.54 CFM or 71.9 LPM at 0 PSI, while Smittybilt 2781 has 5.65 CFM or 159.99 LPM at 0 PSI. When it comes to this aspect, the latter is more impressive.

Maximum Continuous Cycle Time

Viair 400P has a maximum continuous cycle time of 10 minutes at 100 PSI with a 72 °F temperature, while Smittybilt 2781 runs for 30 minutes at 29 PSI with the same temperature.

As for their rest time, let 400P sit for 30 mins and 2781 for 20 mins. They also have a 25% and a 60% duty cycle, respectively.

Frequently Asked Questions

Can air compressors be dangerous?

Air compressors are beneficial in many ways and useful for various things. However, if they are not properly maintained and used, they might be dangerous.

Make sure to check the manual beforehand and read the DOs and DONTs of the product to ensure safety.

When should I replace the tank of my air compressors?

Fixed tanks only fail if you lack proper maintenance like draining the water regularly.

It may cause internal rust and damage your tank. But if your tank is 40-50 years old, it might be right to replace the tank already.

What PSI is dangerous to the skin?

Pressure as low as 100 PSI can cause serious injuries when it hits your skin.

How often should I change the oil?

You should change the oil every 3 months, ideally. But if you can’t, it’s important to do it at least once a year.

What do you mean by the duty cycle of a compressor?

A duty cycle refers to the rating in which the compressors run as compared to the overall cycle (total time running and stopped).

Final Words

So, which one is better? Well, the answer to this merely depends on your needs and preferences.

Hopefully, you have one in mind after going through this Viair 400P vs. Smittybilt review.

Both products have shown outstanding performance and quality because of their features that help you with your everyday tasks for sure.