The Stihl DIRT BOSS® RB 400 is a gas-powered pressure washer offering a maximum water pressure of 2700 PSI and flow of 2.7 GPM. (Read full specs)
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Features and Specifications
| Fuel | Gas-Powered |
|---|---|
| Handling | Hand Truck |
| Water | Cold (125°F max.) |
| PSI | 2700 |
| GPM | 2.7 |
| Cleaning Units | 7290 |
| Engine | 196cc 6.5 HP Kohler SH265 4-stroke OHV |
| Pump | Axial |
| Frame | Steel tubing |
|---|---|
| Soap injection | Via siphon hose |
| Soap dilution | No |
| Nozzles | 0°, 15°, 25°, 40°, Soap |
| Quick connect nozzles | Yes |
| Onboard storage | Yes |
| Hose | 25 ft |
| Hose storage | Hooks |
| Dimensions (D x W x H) | Approx. 28.5 x 27.5 x 39.5 in |
|---|---|
| Weight | 90 lbs |
| Wheels | 2 wheels, pneumatic |
| Included accessories | Oil, wand, spray gun, high pressure hose, soap hose, 5 nozzles |
| Security | Low oil, trigger lock and thermal relief valve |
| Emissions | EPA |
| Warranty | 2 years |
| UPC | 886661293711 |
Unlike many websites, we did our best to research each of the specs above. That being said, we are not immune to making the occasional mistake or omission. Should you notice any missing or incorrect values, don't hesitate to suggest improvements so we can address the issue.
Description
Zoom on the Stihl RB 400
In a nutshell, the Stihl RB 400 is a medium duty pressure washer, which not only offers an all-around versatile cleaning experience, but that also allows:
- spot cleaning of hard, unpainted surfaces, reaching high areas, and removing stubborn stains
- comprehensive cleaning of hard surfaces, vehicle washing, and readying surfaces for painting
- delicate surface cleaning, andbroad area cleaning with reduced pressure
- using cleaning solutions, and rinsing surfaces to remove residue
The following sections will present you in detail its power characteristics and design, its main features and all the additional features it has to offer.
Power
The Stihl RB 400
With a 196cc (6.5 hp) engine, its axial pump delivers a pressure of 2700 PSI (roughly 45 times more than a standard garden hose) and a flow of up to 2.7 GPM (values claimed by the manufacturer), resulting in the Stihl RB 400's cleaning power of 7290 Cleaning Units.
Initiating the Kohler SH265 engine of this gas pressure washer is achieved through a classic pull-start process.
Fuel for the pressure washer is housed in a tank capable of holding up to 0.95 gallon of gasoline..
Design & Handling
The Stihl RB 400 is very mobile, due to its hand truck design and approximate dimensions of D28.5 x W27.5 x H39.5 in. The robust steel tubing frame guarantees longevity of the assembly, providing stability and protection for internal components, even under demanding working conditions. The folding handle enhances its mobility, while allowing for a convenient storage.
At 90 lbs, this unit's substantial weight makes it quite a challenge for users to lift and maneuver, particularly on uneven surfaces where its heft can become even more apparent. The main contributors to its weight are its 196cc Kohler SH265 engine and steel tubing frame. However, the incorporation of two pneumatic wheels makes navigating the RB 400 less cumbersome, even on uneven terrain.
Main Features
The Stihl RB 400
The Stihl RB 400's package includes a spray gun, a wand, a pressure hose, 5 nozzles and a detergent injection feature, with a more detailed description below.
- Soap injection: Despite the absence of a soap tank, detergent supply is facilitated through the use of a siphon hose. Given the absence of a soap dilution mechanism, users should dilute detergent correctly before operating the Stihl RB 400 pressure washer. The detergent is automatically mixed with the water flow by the pressure washer when a soap nozzle is connected.
- Pressure hose: With a set of convenient hooks, the unit provides a convenient way to store the included 25 ft high-pressure hose when not in use, keeping it organized and readily accessible.
- Spray gun and wand: A side hook allows for an easy storage of the included classic ergonomic spray gun and its wand.
- Nozzles: Find details on the 5 included nozzles and their recommended surface applications in the table below.
0° | 15° | 25° | 40° | Soap | |
|---|---|---|---|---|---|
| Concrete, brick, masonry | Use with caution | Suitable | Suitable | Suitable | Suitable |
| Siding, gutters, house | Not recommended | Use with caution | Use with caution | Suitable | Suitable |
| Fencing, deck, patio | Not recommended | Use with caution | Use with caution | Suitable | Suitable |
| Lawn equipment, boat, RV | Not recommended | Use with caution | Use with caution | Use with caution | Suitable |
Important note: The shapes of the depicted nozzles serve for illustration purposes only and may vary. Symbols used include a red cross for 'Not recommended,' a green check for 'Suitable,' and an orange check for 'Use with caution.'
Other Features
The Stihl RB 400
- Onboard storage: Stay prepared for any job with Stihl RB 400's handy storage area, which allows you to neatly store any nozzles and accessories which you may need for the job.
- Safety: Safety of operation is enhanced by a thermal relief valve (which helps to prevent internal pump damage), a trigger lock mechanism (which prevents accidental operation) and a low oil protection.
- Accessories: Besides the usual owner's manual (opens in a new tab) and documentation to get you promptly started, the Stihl RB 400 comes with oil, wand, spray gun, soap hose and pressure hose.
Product Videos
The Stihl RB 400's performance versus other pressure washers
The following charts are provided to give you an idea of how the key specs of the Stihl RB 400 compare to similarly priced pressure washers.
- The Stihl RB 400, boasting 2700 PSI, achieves a lower pressure compared to other gas-powered pressure washers in the $775-900 price bracket. If your priority is the highest possible power of the water stream, in this price range, we suggest checking out the Westinghouse WPX4400, which reaches up to 4400 PSI.
- When measured against items within the price range mentioned earlier, this washer, with its 2.7 GPM, falls on the lower end of achievable water flow rates. If you’re after the highest rinsing efficiency, one of the units with the highest water flow in the current price range is the Westinghouse WPX4400, that can deliver up to 4.2 GPM.
- The RB 400 has 7290 Cleaning Units (PSI X GPM), which can be considered low in comparison to other gas-powered devices of this price. If the highest overall cleaning power is a priority, the Westinghouse WPX4400 and its 18480 Cleaning Units are notable for their higher potential cleaning efficiency compared to units in the same price range.
Here's a list of the most popular specific comparisons:
Price comparison
As you can see from these interactive charts, when compared to other gas-powered washers between 7000 and 7500 Cleaning Units, the Stihl RB 400 is on the expensive side of the price range.
While certainly not the cheapest of its cleaning power range, purchasing it could most likely also mean enjoying the reliability of a high-end product.
The bottom line
- Good range of nozzles included
- Onboard storage
- Several security features
- On the expensive side
- No soap tank
- No detergent dilution mechanism
- Low PSI for the price
- Low GPM for the price
- Low CU for the price
About Stihl
Since revolutionizing the forestry industry in 1926 with the invention of the first two-person electric chainsaw, STIHL has become one of the top-selling brands of outdoor power equipment in the US and around the world. Their ever-growing product line includes gas-powered, corded-electric and battery products. Made in the USA and in China by over 2,000 dedicated employees at their state-of-the-art, dedicated, manufacturing facilities in Virginia Beach, VA, and in Qingdao, STIHL products are sold by local, authorized dealers in over 80 countries.
Warranty Information
The Stihl RB 400 is covered under a warranty for up to 2 years. This warranty may be limited and may not cover all parts of the unit.
For more information about the warranty of Stihl pressure washers, please consult Stihl's warranty policies (opens in a new tab). Alternatively, you can also contact their Customer Support: 1-800-467-8445.
Not happy with performance. Not the stihl quality I’m used to in chain saws . The only thing that’s Stihl is the name all parts are sourced
I bought the 400 last year maybe used it 6 to 7 times it will not hold water pressure zero leaks anywhere what do I need to do to the pump to make it work correctly?
Very poorly designed, You can not just pull back on the handle to move the unit you must place you foot on the frame to get it to tilt back. Very difficult to get the pressure hose off the pump as well as the wand. 25 feet of hose is not very good it is too short, requiring a lot of moving when washing the house. Kohler is a good engine but you can not shot off the gas supply to run the carburetor dry, considering the relatively high price for its capacity you would hope it would be more user friendly.