The battery clamps were a notch or two above what one normally expects on a portable compressor. They are attached to the end of 10 gauge wiring that also includes a 50 amp in-line fuse. The compressor is also protected by an internal thermal overload device that will shut down the compressor if the heat build becomes excessive. Although I mentioned earlier that you may be able to skip the owners manual, I do suggest you read it as it does contain some of the dos and don'ts for using the compressor.
The air hose has a quick disconnect that attaches it to the compressor and also makes it easy to disconnect the hose for storage. The business end of the air hose has a nice quality clamp on air chuck that doesn't leak when you snap it onto the tire's valve stem. The handle of the air chuck has a feature in it that allows you to deflate the tire should you fill it a little too full....a nice touch. The in-line pressure gauge maxes out at 120 PSI and appears to be accurate. I compared it against the gauge I normally use (I am not saying that one is calibrated) for airing up my tires and they both read the same when used on one of my tires.
One thing I did notice while reading through the compressor specs was the maximum ambient air temp which happens to be 158 degrees F. I've seen folks mount compressors under the hood. For this compressor, that would not be a suitable location as under hood temps will easily exceed 158 degrees F. Keep it some place else, folks!
I did a few air-up times and found it to perform pretty good. On my 35"x12.5" MT/R tire, which I aired down to 10 PSI, it filled the tire to 30 PSI in 2 minutes, 25 seconds. My ExtremeAire does the same tire from 10 to 30 PSI in 2 minutes flat.....and it makes a fair amount of noise while doing so.
Where my compressor really pushes past the 440P is in the duty cycle rating. My compressor runs 100% duty cycle. The 440P can be run for 30 minutes at 30 PSI @ 72 degrees F. I didn't seen any specs on how this rating is down graded when the ambient temp goes up, but for here in Arizona, airing up at 115 degrees F would not be at all uncommon. None the less, the 440P should be able to air up 3 vehicles with 35"x12.5" tires before its time to let it cool down (that would be pushing it right about to the max time limit).
I have to admit that I was quite impressed with this little 12V compressor that will suck down just short of 38 amps when it nears its max pressure rating of 150 PSI (which by the way is then flowing less than 1 CFM). The VIAIR web site states the 440P flows 2.26 CFM at 30 PSI and 2.79 CFM at 10 PSI.
I've no idea how this compressor does for the long haul. I recently retired my QuickAir 2 compressor after 6+ years of service and it is still doing a good job of airing up tires. If the 440P lasts for 6+ years, then I would say you got a good deal and then some. If my ExtremeAire should require replacement, I will certainly look at these higher end Viair compressors as a potential replacement.
Good trails and remember to TREADLightly!
I received an e-mail today from a site user who had read this review. He wanted to pass along a personal experience he had concerning the Viair customer support folks and the coiled air hose that came with his 400C compressor. He wrote....
I've never seen a coiled hose break and when I contacted VIAIR, they had not seen one either. Long story short, they immediately sent me a replacement hose (the black braided coil hose) and asked several questions about the conditions present when the plastic hose broke. Finally, they asked me to send the broken hose to them (they are paying the shipping) so they can evaluate why the hose broke, All through our correspondence, I have been impressed with their concern that a product of theirs failed. I have long been impressed with the quality of their compressors, fittings and accessories; now I can add their customer support to the list.
So I say thanks for sharing your customer service experience with all of us. It is always good to hear about this good kind of service.
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