Living on the road full-time in an RV and traveling around the country means you have your whole life riding on your tires. The best way to prevent a blowout is by maintaining proper tire inflation. For years, we used my (Brandon's) scuba tanks to air up the tires and this worked very well except for one problem. When the tanks were empty, we couldn't fill up the tires anymore. As we started pushing further and further off the beaten path, this began to take us far away from scuba shops where we could refill the tanks. So, we decided it was time to get a proper compressor. Continue reading for our Viair 400P-RV review.
The Viair 400P compressor is sold in 2 different kits.
The basic 400P kit is suitable for airing up cars and trucks or shorter RVs like vans, class Cs, or small motorhomes without a towed vehicle.
The 400P-RV kit has the exact same compressor and hose, but also includes an extension hose that allows you to reach up to 60 feet from the compressor, a twist on air chuck that allows you to connect the hose to your tire so you can stand up while filling your tires, and a 45 degree inflation chuck for hard to inflate dual rear tires. This kit is perfect for long RVs like Class A motorhomes, truck and trailer combinations, or any motorized RV that is towing a car.
Viair 400P vs 450P Compressors
Both of these compressors are capable of filling tires up to 150psi - so they'll have no problem with the largest motorhome tires.
The only difference between these compressors is that the 450P runs at a 100% duty cycle and the 400P runs at a 33% duty cycle.
So, why not choose the 450P and get the maximum duty cycle?
It's not that simple!
Duty Cycle Isn't Everything!
Wait a minute! Don't just look at the duty cycle.
In simple terms, the 100% duty cycle of the 450P means you can run it continuously for about an hour before you need to cool it down.
The 33% duty cycle of the 400p means you can only run it about 20 minutes before you need to let it cool down for 40 minutes or so.
Here's The Catch!
In order to make the 450P run at 100% duty cycle, it runs SLOWER!
The 400P at a 33% duty cycle will inflate your tires faster.
And because both models have an automatic shutoff when you aren't inflating, it's highly unlikely in the RV world or off-roading world that you would ever run it for 20 minutes straight.
If you did get to a point where you are running the compressor for that long then you probably have some other serious issue that needs to be dealt with.
For that reason, we went with the Viair 400P-RV. It has a shorter duty cycle, but it works faster and that's why we recommend it!
On top of that, we already had plenty of experience using our friend's 400P that we knew we could pump up the tires of multiple off-road vehicles without ever over-heating the compressor.
Alternatives to the Viair 400P-RV
The compressor in this Viair 400P-RV review is not a cheap compressor. But, if you need a durable, small compressor that is capable of filling large RV tires in a reasonable amount of time, it is hard to beat.
If you don't need such a high capacity compressor then Viair has another option:
This is a nice lower cost alternative to the 400P that should still serve you very well. This model would be great for small travel trailer owners, van campers, class B owners and off-road enthusiasts on a budget.
Whatever you do, make sure you have some means of filling up your tires to do your best to avoid a blow out that could ruin a perfectly good trip.