Seaflo 42 Series 3.0 GPM 55 psi
#1 in Under 4 GPMFull review
A strong-value 3 GPM replacement: 55 psi, a bypass and a 4-year warranty for about half the price of the name-brand equivalent.
Amazon $59.32$59.32
The Seaflo 42 Series 3.0 GPM 55 psi is the better RV water pump overall, rated 3.7 to 3.3. The Seaflo 42 Series 3.0 GPM 55 psi leads on warranty and value. The PowerMax 3.0 GPM 55 psi RV Pump wins on features. The Seaflo 42 Series 3.0 GPM 55 psi costs $14.68 less ($59.32 vs $74).
Prices were last checked November 9, 2026. Product prices and availability are accurate as of that date and are subject to change; the price and availability shown on Amazon or the retailer's site at the time of purchase apply. As an Amazon Associate we earn from qualifying purchases.
PowerMax 3.0 GPM 55 psi RV Pump
#3 in Under 4 GPMFull review
A cheaper stand-in for the Shurflo 4008 with the same flow, pressure and bypass. Seaflo’s 42 Series is cheaper still with a longer warranty.
Amazon $74$74
Which should you buy?
- Choose the Seaflo 42 Series 3.0 GPM 55 psi for warranty (4-year warranty vs 2-year warranty) and value ($19.77 per GPM ($59.32, 3 GPM) vs $24.67 per GPM ($74, 3 GPM)).
- Choose the PowerMax 3.0 GPM 55 psi RV Pump for features (internal bypass, runs dry without damage, thermal protection vs internal bypass, runs dry without damage).
Scores side by side
Each factor is scored 0-100 against the same fixed reference points for every under 4 GPM RV water pump; a clear win is highlighted. How we rank explains each one.
| Factor weight | Seaflo 42 Series 3.0 GPM 55 psi | PowerMax 3.0 GPM 55 psi RV Pump |
|---|---|---|
| Overall rating | 3.7/5 | 3.3/5 |
| Value 25% | 82 $19.77 per GPM ($59.32, 3 GPM) | 68 $24.67 per GPM ($74, 3 GPM) |
| Flow 20% | 25 3 GPM rated open flow | 25 3 GPM rated open flow |
| Pressure 15% | 71 55 psi shut-off | 71 55 psi shut-off |
| Efficiency 10% | 51 0.43 GPM per amp (7 A max) | 50 maximum current draw not published (neutral score used) |
| Features 15% | 40 internal bypass, runs dry without damage | 55 internal bypass, runs dry without damage, thermal protection |
| Warranty 15% | 100 4-year warranty | 33 2-year warranty |
Specifications
| Seaflo 42 Series 3.0 GPM 55 psi | PowerMax 3.0 GPM 55 psi RV Pump | |
|---|---|---|
| Performance | ||
| Rated open flow | 3 GPM | 3 GPM |
| Shut-off pressure | 55 psi | 55 psi |
| Max current draw | 7 A | - |
| Price per GPM | $19.77 | $24.67 |
| Self-priming lift | 6 ft | 9 ft |
| Features | ||
| Control | Pressure switch | Pressure switch |
| Internal bypass | Yes | Yes |
| Runs dry | Yes | Yes |
| Thermal protection | - | Yes |
| Build | ||
| Weight | - | 4 lb |
| Warranty | 4 years | 2 years |