Steele showcases industry-first magnesium alloy piston
Like the MS 500i, which was the world's first chainsaw with electronically controlled fuel injection, the Stihl MS 400 CM is also a first. This saw showcases a magnesium alloy piston that increases power and torque without adding any extra weight. Plus, with Stihl M-Tronic engine technology, tree care and forestry professionals get a powerful chainsaw that delivers low emissions and improved fuel efficiency in all operating conditions.
Notable features
The proverbial "people's talk" here is apparently that the engineering team replaced the standard aluminum pistons with magnesium alloy pistons. Steele tells us that this particular innovation increases engine displacement by 13 percent, delivering more power and torque. However, despite the increased performance (5.4 hp), the STIHL MS 400 CM maintains an excellent power-to-weight ratio (12.8 lbs)

In addition, the STIHL MS 400 CM chainsaw is equipped with the M-Tronic intelligent engine management system. This innovation does away with the carburetor's low- and high-speed adjustment screws; instead, it electronically adjusts the fuel and air mixture in the carb based on any operating conditions. This "smart" engine continuously monitors operating conditions and chain speed, optimizing engine performance while saving fuel.
Thanks to the M-Tronic system, this STIHL MS 400 CM offers excellent acceleration even after a cold start. It will even remember the last time you set it under the same conditions and reset to it every time the engine hits full power.
Finally, the other "big problem" here is the filtration system. The Stihl MS 400 CM starts with a pre-separation air filtration system. This technology doubles the time between air filter cleanings by using centrifugal force to suck out heavier debris before it hits the air filter. When there is less dirt on the filter, you won't need to clean it as often. When it's time to service the HD2 air filter, you can simply clean it rather than completely replace it.
other features
- ElastoStart starter handles offer built-in shock absorbers to help reduce the force required to pull the saw
- Quickstop chain brake stops the chain on kickback, stopping the chain in a fraction of a second
- Adjustable auto lubricator allows you to adjust rod and chain lubricant based on rod length and cutting conditions
- Ematic lubrication system keeps rods and chains, rivets and drive holes lubricated while reducing oil consumption by up to 50%
- Anti-vibration system reduces operator fatigue
- fuel and oil cap retainer
- side entry chain tensioner
- Master control lever provides a single lever to operate choke, activate throttle lock and switch
- Pressure relief valve reduces compression of the combustion chamber at start-up, making it easier to pull to start the chainsaw
- Winter/summer shutter keeps carburetor running at optimum temperature year-round and prevents carburetor from freezing when operating at cooler temperatures
Price
When it actually debuts, you'll be able to buy the Stihl MS 400 CM chainsaw at any Stihl dealer or directly from the Stihl website. Like Stihl's other pneumatic chainsaws, it comes with a 1-year residential or 3-month commercial warranty. With the 20-inch bar and chain, it should retail for around $869.99.
For more information, including where to find your nearest Stihl dealer, click here.
STIHL Chainsaw Specifications
- Model: STIHL MS 400 CM
- Displacement: 66.8 cc (4.1 in3 )
- Engine Power: 4.0 kW (5.4 hp)
- Weight: 5.8 kg (12.8 lbs)
- Fuel Capacity: 600cc (20.3 oz)
- Oil Capacity: 325 cc (11 oz)
- Guide rod length: 40 to 63 cm (16" to 25")
- Warranty: 1 Year Residential/3 Months Professional
- Price: $869.99 with 20" guide bar and chain