The cheapest way to a 3 GPM pump with a 4-year warranty. Buy it for a travel trailer when a firm 55 psi shower isn’t a priority.
Amazon $52.99The Seaflo 33 Series 3.0 GPM 45 psi is the better RV water pump overall, rated 3.6 to 3.3. The Seaflo 33 Series 3.0 GPM 45 psi leads on warranty and value. The PowerMax 3.0 GPM 55 psi RV Pump wins on pressure and features. The Seaflo 33 Series 3.0 GPM 45 psi costs $21.01 less ($52.99 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.
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 $74Which should you buy?
- Choose the Seaflo 33 Series 3.0 GPM 45 psi for warranty (4-year warranty vs 2-year warranty) and value ($17.66 per GPM ($52.99, 3 GPM) vs $24.67 per GPM ($74, 3 GPM)).
- Choose the PowerMax 3.0 GPM 55 psi RV Pump for pressure (55 psi shut-off vs 45 psi shut-off) and features (internal bypass, runs dry without damage, thermal protection vs runs dry without damage, thermal protection, strainer included).
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 33 Series 3.0 GPM 45 psi | PowerMax 3.0 GPM 55 psi RV Pump |
|---|---|---|
| Overall rating | 3.6/5 | 3.3/5 |
| Value 25% | 89 $17.66 per GPM ($52.99, 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% | 43 45 psi shut-off | 71 55 psi shut-off |
| Efficiency 10% | 50 maximum current draw not published (neutral score used) | 50 maximum current draw not published (neutral score used) |
| Features 15% | 45 runs dry without damage, thermal protection, strainer included | 55 internal bypass, runs dry without damage, thermal protection |
| Warranty 15% | 100 4-year warranty | 33 2-year warranty |
Specifications
| Seaflo 33 Series 3.0 GPM 45 psi | PowerMax 3.0 GPM 55 psi RV Pump | |
|---|---|---|
| Performance | ||
| Rated open flow | 3 GPM | 3 GPM |
| Shut-off pressure | 45 psi | 55 psi |
| Price per GPM | $17.66 | $24.67 |
| Self-priming lift | 6 ft | 9 ft |
| Features | ||
| Control | Pressure switch | Pressure switch |
| Diaphragm chambers | 3 | - |
| Internal bypass | - | Yes |
| Runs dry | Yes | Yes |
| Thermal protection | Yes | Yes |
| Strainer included | Yes | - |
| Build | ||
| Weight | - | 4 lb |
| Warranty | 4 years | 2 years |
