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)
Zoom on the Stihl RB 400
In summary, the Stihl RB 400 is a medium duty pressure washer, that offers an all-around versatile cleaning experience, and also:
- spot cleaning of hard, paint-free surfaces and out-of-reach areas
- intense cleaning of tough, paintless surfaces
- cleaning of painted and fragile surfaces
- use of detergent and cleaning solutions
Powered by a 196 cc (6.5 hp) engine, its axial pump can deliver a pressure of 2700 PSI (around 45 times more than a standard garden hose) and a flow of up to 2.7 GPM (values claimed by the manufacturer). Combined, these values mean that the Stihl RB 400 has a cleaning power of 7290 Cleaning Units.
The Kohler SH265 engine of this gas-powered pressure washer relies on an old-school pull-start mechanism to get started.
The fuel is stored in a tank, which can hold 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 and sturdy steel tubing frame offers longevity to the assembly. The folding handle enhances its mobility, while allowing for a convenient storage.
The device weighs 90 lbs and thus, is far from lightweight. Transporting and manually lifting it may therefore pose a challenge. Its 196 cc Kohler SH265 engine and steel tubing frame are mainly responsible for its heavy weight. However, the unit is mobile thanks to its two pneumatic wheels, which add to its movability and allow it to be manipulated smoothly on the job.
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: While the device doesn't feature a soap tank, detergent supply is ensured by a siphon hose. However, since the Stihl RB 400 does not feature a soap dilution mechanism, you'll have to make sure your detergent is correctly diluted before use. The detergent is automatically added to the water when a soap nozzle is connected.
- Pressure hose: The included 25 ft high-pressure hose can be neatly stored on the unit when idle thanks to a set of convenient hooks.
- Spray gun and wand: A side hook enables you to easily store the included classic ergonomic spray gun and its wand.
- Nozzles: The 5 nozzles included with the device, and the respective surfaces which they’re the most suitable for, are shown in the following table.
|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|
Note: The shape of the nozzles above is for illustration purposes only and may differ.
Red cross: Not recommended. Green check: Suitable. Orange check: Use with caution.
- Onboard storage: The Stihl RB 400's handy storage area lets you store nozzles and accessories, and thus, you’ll be always prepared and have everything necessary for the job at hand.
- Safety: Safety of operation is enhanced by a low oil protection, a trigger lock mechanism (which prevents accidental operation) and a thermal relief valve (which helps to prevent internal pump damage).
- Accessories: Included with the Stihl RB 400 are also the owner's manual (opens in a new tab) and some basic documentation to get you promptly started, along with several accessories, such as wand, oil, pressure hose, spray gun and soap hose.
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 and its 2700 PSI, ranks amongst gas-powered pressure washers with a comparably low pressure output, considering the units that cost between $600 and $700. If the highest possible power of the water stream is your priority, one of the champions in this price range is the Simpson PS60843 with 4400 PSI.
- In the aforementioned price range, the GPM (gallons per minute) of this washer, which can reach 2.7, can be considered in the average. In case you are looking for a device which can most efficiently rinse away debris in the current price range, the Simpson PS60843 has the highest GPM of 4.
- Amongst similarly priced gas-powered devices, the 7290 Cleaning Units (PSI x GPM) of the RB 400 rank as low. If you are after the highest overall cleaning power, the Simpson PS60843 with its 17600 Cleaning Units is one of the products that can achieve the highest cleaning efficiency in this price range.
Here's a list of the most popular specific comparisons:
As you can see from this interactive chart, 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.
Features and Specifications
|Water||Cold (125°F max.)|
|Engine||196 cc 6.5 HP Kohler SH265 4-stroke OHV|
|Soap injection||Via siphon hose|
|Nozzles||0°, 15°, 25°, 40°, Soap|
|Quick connect nozzles||Yes|
(D x W x H)
|Approx. 28.5 x 27.5 x 39.5 in|
|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|
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.
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.
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.