Head-to-head comparison · Tire Inflators
VIAIR 300P vs 400P
Two VIAIR battery-clamp compressors with the same 2.30 CFM airflow, 33% duty cycle at 100 PSI and 25 ft hose. The difference is tire size rating and weight.
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 400P Portable Compressor (40043) wins
The 400P is rated for tires up to 35 inches against 33, which covers more lifted trucks. If your tires are 33 inches or smaller, the 300P gives the same published airflow for 1.7 lb less.
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VIAIR 300P Portable Compressor (30033)
A 150 PSI, 2.30 CFM battery-clamp compressor for tires up to 33 inches, with a 25 ft hose and an IP54 rating, at 8.7 lb.
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 300P Portable Compressor (30033) | VIAIR 400P Portable Compressor (40043)Our pick |
|---|---|---|
| Editorial score | Editorial score:8.2/10 | Editorial score:8.5/10 |
| Best for | Lightest 150 PSI Clamp-On Compressor | 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 | 2.30 CFM at 0 PSI | 2.30 CFM at 0 PSI |
| Duty cycle | 33% at 100 PSI | 33% at 100 PSI |
| Max tire size | Up to 33 in | Up to 35 in |
| Display | Inline 100 PSI gauge on the hose | Inline 100 PSI gauge on the hose |
| Hose length | 25 ft coil hose with 5-in-1 inflator/deflator | 25 ft coil hose with 5-in-1 inflator/deflator |
| Power cord | 8 ft; 30 A max draw | 8 ft; 30 A max draw |
| Included accessories | Carry bag, 3-piece inflation tips kit, Presta valve adaptor, aluminum sand tray, 40 A inline fuse holder | Carry bag, 3-piece inflation tips kit, Presta valve adaptor, sand tray, inline fuse holder |
| Weight | 8.7 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
- 1Max tire size: up to 35 in for the 400P, 33 in for the 300P
- 2Weight: 10.4 lb against 8.7 lb
- 3Airflow: 2.30 CFM at 0 PSI for both
- 4Duty cycle: 33% at 100 PSI for both
- 5Max draw: 30 A for both
Product by product
Pros and cons
VIAIR 300P Portable Compressor (30033)
A lighter VIAIR for trucks, Jeeps and SUVs on tires up to 33 inches, with the same airflow as the 400P. If you run 35-inch tires, buy the 400P.
Pros
- Same 2.30 CFM airflow and 33% duty cycle at 100 PSI as the VIAIR 400P, at 8.7 lb against 10.4 lb
- 25 ft hose reaches all four tires from one spot
- IP54 rating against dust and splashes, per VIAIR
- Thermal overload protector
Cons
- Rated for tires up to 33 inches; the 400P is rated for 35 inches
- No auto shut-off: you watch the gauge and stop it yourself
- Clamps to the battery, so you open the hood every time
- VIAIR does not recommend the included hose in freezing weather
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 400P if
- You run 34- or 35-inch tires.
Choose the VIAIR 300P if
- Your tires are 33 inches or smaller.
- You want the lighter kit with the same published airflow.
- You want VIAIR's IP54 rating, which it lists for the 300P.
Neither has an auto shut-off. For the full range, see our tire inflator list.
Frequently asked questions
- Is the VIAIR 400P faster than the 300P?
- VIAIR lists the same 2.30 CFM at 0 PSI and the same 33% duty cycle at 100 PSI for both. The 400P is rated for larger tires, up to 35 inches against 33.
- Which is lighter?
- The 300P, at 8.7 lb against 10.4 lb for the 400P.
- Do they plug into a 12 V socket?
- No. Both clamp to the vehicle battery and can draw up to 30 A.
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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