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 2.7. The Seaflo 42 Series 3.0 GPM 55 psi leads on value, pressure and features. The Jabsco Par-Max 3 25 psi wins on efficiency. The Seaflo 42 Series 3.0 GPM 55 psi costs $62.16 less ($59.32 vs $121.48).
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.
Jabsco Par-Max 3 25 psi
#8 in Under 4 GPMFull review
A low-pressure pump for boats and gravity-style systems where gentle 25 psi flow is wanted. Most RVs want a 45 to 55 psi pump instead.
Amazon $121.48$121.48
Which should you buy?
- Choose the Seaflo 42 Series 3.0 GPM 55 psi for value ($19.77 per GPM ($59.32, 3 GPM) vs $40.49 per GPM ($121.48, 3 GPM)), pressure (55 psi shut-off vs 25 psi shut-off) and features (internal bypass, runs dry without damage vs none of the listed features).
- Choose the Jabsco Par-Max 3 25 psi for efficiency (0.58 GPM per amp (5.2 A max) vs 0.43 GPM per amp (7 A max)).
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 | Jabsco Par-Max 3 25 psi |
|---|---|---|
| Overall rating | 3.7/5 | 2.7/5 |
| Value 25% | 82 $19.77 per GPM ($59.32, 3 GPM) | 36 $40.49 per GPM ($121.48, 3 GPM) |
| Flow 20% | 25 3 GPM rated open flow | 25 3 GPM rated open flow |
| Pressure 15% | 71 55 psi shut-off | 0 25 psi shut-off |
| Efficiency 10% | 51 0.43 GPM per amp (7 A max) | 93 0.58 GPM per amp (5.2 A max) |
| Features 15% | 40 internal bypass, runs dry without damage | 0 none of the listed features |
| Warranty 15% | 100 4-year warranty | 67 3-year warranty |
Specifications
| Seaflo 42 Series 3.0 GPM 55 psi | Jabsco Par-Max 3 25 psi | |
|---|---|---|
| Performance | ||
| Rated open flow | 3 GPM | 3 GPM |
| Shut-off pressure | 55 psi | 25 psi |
| Max current draw | 7 A | 5.2 A |
| Price per GPM | $19.77 | $40.49 |
| Self-priming lift | 6 ft | 10 ft |
| Features | ||
| Control | Pressure switch | Pressure switch |
| Diaphragm chambers | - | 3 |
| Internal bypass | Yes | - |
| Runs dry | Yes | - |
| Build | ||
| Weight | - | 3.2 lb |
| Warranty | 4 years | 3 years |