Get offers, how-to guides and more when you join the STIHL Email Community.

Sign Up

RB 400 Dirt Boss®

RB 400 Dirt Boss®
A premium pressure washer that combines excellent performance with durable build quality for long-lasting value.

Product Description

When you need a power washer that delivers top performance and can stand up to daily use, choose the STIHL RB 400 Dirt Boss® pressure washer. It features a powerful 196 cc (6.5 hp) engine that can output 2,700 psi of water pressure at 2.7 gallons per minute. It also features the durability STIHL products are known for, with a brass manifold pump design, stainless steel valves and ceramic-coated pistons. There is also a cast-iron engine liner and a built-in shutdown feature when the oil level is low. The RB 400 Dirt Boss® also features an easy start pump system and convenient detergent injector system. And with its 25' no-kink flex hose, you can clean more area without having to move the machine. Finally, the pressure washer uses a wide range of optional cleaning accessories, including rotary surface cleaner, water broom, nozzle options, hose extensions, a gutter cleaner, aluminum wand extension, pivot coupler and official STIHL cleaning agents. When you need to demolish dirt on a daily basis, the Dirt Boss™ handles the pressure with ease.

Model Features


196 cc 12.0 cu. in.)
3.6 L (3.8 qt.)
620 L/h (2.7 gpm)
2,700 psi
41 kg (90 lbs)
724 x 699 x 654 mm (28.5 x 27.5 x 25.75")
724 x 699 x 1003 mm (28.5 x 27.5 x 39.5")

Important Information

WARNING! Improper use of any power tool may cause serious or fatal injury. Read, understand and follow carefully the operating and safety instructions in your instruction manual before using such products.

STIHL products sold through U.S. STIHL Dealers are for distribution in the United States only.


RB 400 Dirt Boss® is rated 4.6 out of 5 by 7.
Rated 5 out of 5 by from The power washer is easy to use, very sturdy and does a great job of cleaning surfaces The power washer is easy to use, very sturdy and does a great job of cleaning surfaces. Love the washer.
Date published: 2017-08-02
Rated 5 out of 5 by from Solid reliable machine Solid, well built machine that will get the job done. Starts on the first pull. Well worth the investment.
Date published: 2017-07-05
Rated 5 out of 5 by from Like a boss The times that I have used this it has been easy to start and worked like a Stihl should.
Date published: 2017-06-05
Rated 5 out of 5 by from Great Product Purchased the RB400 Dirt Boss earlier this week. So far I am very impressed with this machine. Watched the service technician check fluids, then fire it right up on the first pull. The Kohler engine runs very smoothly and it is much quieter in comparison to the engines on pressure washers I've used in the past. I like that the engine kill switch acts as a fuel cut off as well. This seems like a smart feature for a carb motor. STIHL thought this product out and it shows. The connections are simple, quick and do not over tighten with use (be sure to squeeze the wand trigger to release the pressure before you try and disconnect the wand after use). The hose doesn't kink and have a mind of it's own. The trigger on the wand pulls from the top side to reduce fatigue with extended use. The pressure is strong enough to tackle big jobs but smooth enough so that it doesn't wear you out with extended use also.Other features include light weight materials and ergonomic handles that allow one man to load the machine onto a standard full size pickup truck. These features also allow the machine to be maneuvered with very little effort in comparison to other pressure washer models. Longevity is tough to determine at this point, but if this machine is anything like the 7 other STIHL machines I've purchased, it will be cleaning my house, porch and driveway for a long time.
Date published: 2017-05-19
Rated 2 out of 5 by from Pump leaking on first use Well I decided to buy the new Stihl pressure washer because everything else I have from them is top-notch and last forever. Well I can't say this for the new RB - 400 and I knew coming in with it being brand new they would probably have some small Kinks to work out anyway I used it the first time for about 2 hours washing my driveway off I'm always very particular with all my equipment as I clean everything off before I put it up as I was cleaning it I noticed black Grease below the pump two decent-sized puddles. I'm not sure where it's coming from and worst of all it's just disappointing after spending so much money on a product and have it fail on you the first use. Hopefully I can get it fixed but it's not a good sign so far
Date published: 2017-04-23
Rated 5 out of 5 by from This thing is awesome pressure washed my siding and 30,000 gallon concrete pool no problem . Deffinitely recomend this product!!!
Date published: 2017-04-13
Rated 5 out of 5 by from Stout machine. Nice quality made product. Solidly built. No plastic. Unable to determine dependability as it is brand new, starts easy.
Date published: 2017-04-12
  • y_2017, m_8, d_18, h_7
  • bvseo_bulk, prod_bvrr, vn_bulk_1.0.0-hotfix-1
  • cp_1, bvpage1
  • co_hasreviews, tv_0, tr_7
  • loc_en_US, sid_rb400, prod, sort_[SortEntry(order=FEATURED, direction=DESCENDING), SortEntry(order=SUBMISSION_TIME, direction=DESCENDING)]
  • clientName_stihl

You Will Also Need

For Your Safety


Product Instruction Manual (PDF)

STIHL Limited Warranty

Contact Us


My Servicing Dealer