Head-to-head comparison · Tire Inflators
VIAIR 450P-RV Automatic vs 400P
Two 150 PSI VIAIR compressors that clamp to the vehicle battery. The 450P-RV runs continuously and shuts off by itself; the 400P moves more air for big off-road tires.
By Watt Versus Editorial· Updated
This page was drafted with AI assistance from manufacturers' specs and manuals, and is checked by our editor.
Why the VIAIR 450P-RV Automatic Portable Compressor (45053) wins
For RVs, trailers and dual rear wheels, the 450P-RV wins: a 100% duty cycle at 100 PSI, automatic shut-off and 60 ft of hose. Choose the 400P to air up 35-inch off-road tires faster: 2.30 CFM against 1.80.
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VIAIR 450P-RV Automatic Portable Compressor (45053)
A 150 PSI clamp-on compressor with a 100% duty cycle at 100 PSI, automatic shut-off and 60 ft of hose for RV and dual rear wheels.
VIAIR 400P Portable Compressor (40043)
A 150 PSI, 2.3 CFM compressor that clamps to the vehicle battery, built for truck and off-road tires up to 35 inches.
Side-by-side
Specs compared
| Specification | VIAIR 450P-RV Automatic Portable Compressor (45053)Our pick | VIAIR 400P Portable Compressor (40043) |
|---|---|---|
| Editorial score | Editorial score:8.4/10 | Editorial score:8.5/10 |
| Best for | Best for RV and Dually Tires | Best for 35-Inch Tires |
| Max pressure | 150 PSI | 150 PSI |
| Power source | 12 V vehicle battery, via dual battery clamps | 12 V vehicle battery, via dual battery clamps |
| Battery | Not needed (runs from the vehicle battery) | Not needed (runs from the vehicle battery) |
| Airflow | 1.80 CFM at 0 PSI | 2.30 CFM at 0 PSI |
| Duty cycle | 100% at 100 PSI | 33% at 100 PSI |
| Max tire size | Not given in inches; VIAIR markets it for RV and commercial tires | Up to 35 in |
| Display | Inflation gun with 160 PSI inline gauge | Inline 100 PSI gauge on the hose |
| Hose length | 30 ft primary plus 30 ft extension coil hose | 25 ft coil hose with 5-in-1 inflator/deflator |
| Power cord | 8 ft; 23 A max draw | 8 ft; 30 A max draw |
| Auto shut-off | Yes | — |
| Included accessories | 45-degree chuck for dual rear wheels, 90-degree twist-on chuck, carry bag, inflation tips, Presta valve adaptor, sand tray | Carry bag, 3-piece inflation tips kit, Presta valve adaptor, sand tray, inline fuse holder |
| Water and dust rating | IP54 | — |
| Weight | 13.05 lb | 10.4 lb |
| Warranty | 1 year | 1 year |
| Where to buy | Check Latest Price on Amazon (paid link) | Check Latest Price on Amazon (paid link) |
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At a glance
Key differences
- 1Duty cycle: 100% at 100 PSI against 33%
- 2Airflow: 1.80 CFM against 2.30 CFM at 0 PSI
- 3Auto shut-off: yes against no
- 4Hose: 30 ft plus a 30 ft extension against 25 ft
- 5Weight: 13.05 lb against 10.4 lb
Product by product
Pros and cons
VIAIR 450P-RV Automatic Portable Compressor (45053)
The VIAIR to buy for motorhomes, travel trailers and dual-rear-wheel trucks: it can run continuously and stops itself at your pressure. For airing up 35-inch off-road tires fast, the 400P moves more air.
Pros
- 100% duty cycle at 100 PSI: VIAIR says it can run for up to an hour
- Automatic shut-off, which the 300P and 400P lack
- 60 ft of hose and a 45-degree chuck reach every tire on a motorhome or dually
- Gas-station-style gun with a 160 PSI gauge
Cons
- 1.80 CFM, below the 2.30 CFM of the 400P, so it is not the fastest for big off-road tires
- 13.05 lb, heavier than VIAIR's 300P (8.7 lb) and 400P (10.4 lb)
- Clamps to the battery only; no 12 V socket plug
VIAIR 400P Portable Compressor (40043)
The inflator for big truck and off-road tires: it moves far more air than the cordless tools here. For quick top-offs on a car, a cordless unit is less hassle.
Pros
- 2.3 CFM of airflow, against 1.97 CFM for the 88P; the cordless tools publish no airflow figure
- Rated for tires up to 35 inches: the pick for lifted trucks and airing back up after off-road trips
- 25 ft hose reaches all four tires and a trailer from one spot
- 5-in-1 hose head lets you let air out and check pressure as well
Cons
- 10.4 lb and clamps to the battery, so it is not a quick glovebox top-off tool
- No auto shut-off: you watch the gauge and stop it yourself
- Only a 1-year warranty
Choose the VIAIR 450P-RV Automatic if
- You fill motorhome, trailer or dually tires at high pressure.
- You want the compressor to stop at your set pressure.
- You need reach: 60 ft of hose and a 45-degree chuck for inner duals.
Choose the VIAIR 400P if
- You air up off-road tires up to 35 inches after the trail.
- You want the lighter kit with more airflow.
For smaller tires, the 300P is lighter still; see VIAIR 300P vs 400P.
Frequently asked questions
- Which VIAIR is better for an RV?
- The 450P-RV Automatic: VIAIR rates it at a 100% duty cycle at 100 PSI with automatic shut-off and 60 ft of hose.
- Which is faster?
- The 400P lists more free airflow, 2.30 CFM against 1.80 CFM at 0 PSI, but it has a 33% duty cycle at 100 PSI.
- Do both clamp to the battery?
- Yes. Neither plugs into a 12 V socket.
Sources
The specifications and claims on this page come from these manufacturer documents. Figures are the manufacturers' own unless the text says otherwise.
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