facebook-pixel
Free residential delivery on every order 30-day returns and a 3-year warranty
Commercial Gas · 3600 PSI In stock · ships from Dallas

Simpson ALH3425 Aluminum 3600 PSI 2.5 GPM Honda GX200 Commercial Gas Pressure Washer

The Simpson ALH3425 Aluminum Series pressure washer is engineered for demanding commercial contracting, paint prep, property washing, and equipment maintenance.
5.0 (4 reviews)
$229.00 $849.00 SAVE $620.00 (73% OFF)
In stock · ready to ship Ships tomorrow Order today and it leaves our Dallas, TX warehouse tomorrow.
Tracking number sent by email as soon as the freight carrier picks up your order.
Secure, encrypted checkout
  • 3-year warranty
  • 30-day returns
  • Free delivery
Max Pressure
3,600 PSI
Commercial deep cleaning
Water Flow
2.5 GPM
Fast coverage rate
Engine
Honda GX200
196cc commercial OHV
Pump
AAA Triplex
Industrial ceramic plunger
Overview

Simpson ALH3425 Aluminum 3600 PSI 2.5 GPM Honda GX200 Commercial Gas Pressure Washer

The Simpson ALH3425 Aluminum Series pressure washer is engineered for demanding commercial contracting, paint prep, property washing, and equipment maintenance. Built on a lightweight, aircraft-grade extruded aluminum frame that eliminates rust and provides superior corrosion resistance. Powered by a commercial-duty Honda GX200 OHV engine paired with an industrial AAA triplex plunger pump with PowerBoost technology, it delivers a blistering 3,600 PSI at 2.5 GPM. Includes a 35-foot MorFlex non-marring steel-braided hose, professional ergonomic spray gun, and 5 quick-connect spray tips.

  • 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.
Simpson ALH3425 Aluminum 3600 PSI 2.5 GPM Honda GX200 Commercial Gas Pressure Washer
Simpson ALH3425 Pressure Washer — Commercial Honda GX200 Engine
Simpson ALH3425 Pressure Washer · Feature 1

Commercial Honda GX200 Engine

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.

Simpson ALH3425 Pressure Washer — Aircraft-Grade Aluminum Frame
Simpson ALH3425 Pressure Washer · Feature 2

Aircraft-Grade Aluminum Frame

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.

Simpson ALH3425 Pressure Washer — 10-Inch Pneumatic Tires
Simpson ALH3425 Pressure Washer · Feature 3

10-Inch Pneumatic Tires

10-Inch Pneumatic Tires: Large pneumatic tires on steel ball-bearing hubs easily roll over mud, gravel, steps, and rough terrain.

Simpson ALH3425 Pressure Washer

Specifications

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
Simpson ALH3425 Pressure Washer

What’s included

These come with the machine.

Customer reviews

Reviews from Simpson ALH3425 Pressure Washer owners.

5.0
Based on 4 reviews
5
100% (4)
4
0% (0)
3
0% (0)
2
0% (0)
1
0% (0)
BN
Bradley N.
Charleston, SC
October 3, 2026
★★★★★

Lightweight, starts first pull, strips concrete effortlessly

I run a residential exterior washing business. The Honda GX200 fires on the very first pull every single morning. The aluminum frame is huge for me because we do a lot of coastal beach houses where steel frames rust out in a year. Strips concrete in a single pass.
JT
Jason T.
Nashville, TN
September 27, 2026
★★★★★

AAA triplex pump is a workhorse

Huge step up from axial cam pumps. The pressure is consistent and doesn't pulse. The 35ft MorFlex hose is flexible and doesn't leave black scuff marks on new concrete.
CM
Craig M.
Indianapolis, IN
September 18, 2026
★★★★★

Best pressure washer I have ever owned

Cleaned a 2,000 sq ft concrete driveway, stone retaining walls, and a large cedar deck. Runs smooth and surprisingly quiet for a 3,600 PSI machine. Worth every dime.
SP
Scott P.
Kansas City, MO
September 10, 2026
★★★★★

Fast delivery from Groundmark

Shipped in a reinforced crate. Assembled the handle in 5 minutes, added the included Honda oil, filled with non-ethanol gas, and worked for 6 hours straight with zero hiccups.
Simpson ALH3425 Pressure Washer

Questions and answers

Can’t find what you need? Send us a message and we’ll get back to you.

Contact us
Why choose the aluminum frame over steel?

Aircraft-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.

Is the Honda GX200 engine commercial grade?

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.

Can I use a surface cleaner with this unit?

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.

Does the pump have an unloader valve?

Yes, it features a fully adjustable brass unloader valve allowing you to dial down the pressure for delicate surfaces like wood decks and siding.

Can it draw water from a tank or barrel?

Triplex plunger pumps generate natural suction, but gravity-feeding or using pressurized garden hose supply (minimum 4 GPM) is recommended for peak longevity.

What warranty applies?

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.

How does delivery work?

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.

$229.00 In Stock · Free Freight
Simpson ALH3425 Aluminum 3600 PSI 2.5 GPM Honda GX200 Commercial Gas Pressure Washer 1 / 3