Name: Johnson Pump Aqua Jet WPS 3.5
Brand: Johnson Pump
Price: 137.49 USD

A marine pressure pump with a 3-year warranty, for boats where 41 psi is plenty. RV owners after a firmer shower should look at 55 psi pumps.

Price checked November 9, 2026. As an Amazon Associate we earn from qualifying purchases.

Pros

Cons

The Johnson Pump Aqua Jet WPS family

Every Johnson Pump Aqua Jet WPS model we rank, smallest first. Ratings compare each against its own flow.

Model	Flow	Rating	Price
Johnson Pump Aqua Jet WPS 3.5 (this one)	3.5 GPM	2.8/5	$137.49
Johnson Pump Aqua Jet WPS 4.0	4 GPM	2.8/5	$185.09

How it scores

The rating comes from 6 measured or published factors, each scored 0-100 against fixed reference points for its flow. How we rank explains each one.

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.

$74

3 GPM55 psi

A long-running OEM triplex pump for trailers and campers. It costs more than importer pumps with a longer warranty.

$103.59

2.9 GPM50 psi

A dealer-friendly 3 GPM replacement from a big RV parts maker. Seaflo’s 42 Series gives the same flow and more pressure for less.

$105.95

3 GPM50 psi9.5 A