The Simpson ALH3425 Aluminum Series pressure washer is engineered for demanding commercial contracting, paint prep, deck restoration, heavy equipment cleaning, and property maintenance. Built on a rugged, lightweight aircraft-grade aluminum frame, it completely eliminates rust and frame corrosion while weighing significantly less than steel competitors. At the heart of the ALH3425 is the commercial-standard Honda GX200 4-stroke OHV engine, known globally for quick, effortless starts, exceptional fuel economy, and legendary jobsite durability. The engine is paired with an industrial-grade AAA triplex plunger pump featuring PowerBoost technology that delivers higher pressure directly at the nozzle tip without overloading the pump head. The unit comes equipped with a 35-foot MorFlex steel-braided non-marring high-pressure hose, an ergonomic professional spray gun with 16-inch steel wand, 10-inch premium pneumatic tires with ball bearings, and five quick-connect spray nozzles (0°, 15°, 25°, 40°, and low-pressure soap applicators).
Commercial Honda GX200 Engine: Legendary commercial 196cc OHV Honda engine with cast iron cylinder sleeve, low-oil shutdown, and easy recoil start. Industrial AAA Triplex Plunger Pump: Forged brass manifold, ceramic-coated pistons, and PowerBoost technology delivering 3,600 PSI at 2.5 GPM.
Aircraft-Grade Aluminum Frame: Lightweight extruded aluminum cart resists rust and harsh chemicals; provides dual vibration dampeners. 35-Foot MorFlex Steel Hose: Abrasion-resistant, kink-free, non-marring hose with M22 quick-connect fittings.
10-Inch Pneumatic Tires: Large pneumatic tires on steel ball-bearing hubs easily roll over mud, gravel, steps, and rough terrain.
Figures for this model. If you need a detail that isn’t listed, ask us and we’ll check before you order.
Ask about this model| Operating Pressure | 3,600 PSI |
|---|---|
| Flow Rate | 2.5 GPM (9.5 L/min) |
| Cleaning Units (CU) | 9,000 CU |
| Engine Brand | Honda GX200 Commercial OHV (196cc) |
| Pump Type | AAA Industrial Triplex Plunger Pump with adjustable unloader |
| Frame Material | Aircraft-grade aluminum with brushed finish |
| Hose | 35 ft × 5/16 in MorFlex high-pressure steel-braided non-marring hose |
| Spray Wand | 16-inch steel lance with 1/4" quick-connect collar |
| Spray Nozzles | 5 Quick-connect tips: 0°, 15°, 25°, 40°, and soap |
| Wheels | 10-inch premium pneumatic all-terrain tires |
| Dimensions (L × W × H) | 39" × 21" × 24" |
| Unit Weight | 73.0 lbs (33.1 kg) |
| Warranty | 3-Year Honda Engine Warranty, 5-Year Pump Warranty, 10-Year Frame Warranty |
These come with the machine.
Reviews from Simpson ALH3425 Pressure Washer owners.
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Contact usAircraft-grade aluminum never rusts, resists harsh detergents and salt air, and reduces machine weight by up to 20 lbs, making it much easier to load into a truck bed by yourself.
Yes. Unlike consumer GC engines, the Honda GX series is built for daily commercial use with cast iron cylinder sleeves, ball-bearing supported crankshaft, and heavy-duty air filtration.
Yes. At 3,600 PSI and 2.5 GPM, it is ideal for 15-inch and 16-inch rotary surface cleaners for fast driveway, patio, and parking pad cleaning.
Yes, it features a fully adjustable brass unloader valve allowing you to dial down the pressure for delicate surfaces like wood decks and siding.
Triplex plunger pumps generate natural suction, but gravity-feeding or using pressurized garden hose supply (minimum 4 GPM) is recommended for peak longevity.
You get a 3-year Honda commercial engine warranty, 5-year pump warranty, 10-year frame warranty, and 30-day money-back guarantee from Groundmark.
Delivery is free to residential addresses. Orders ship from our Dallas, TX warehouse, and larger items arrive by freight with a liftgate drop at your curb or driveway. You get a tracking number by email as soon as the carrier picks up your order.
