MS 391 - $579.95 DSRP SAVE $50.00 on select models


Our top-of-the-line chainsaw for farm and ranch.

With an advanced low-emission engine technology, the STIHL MS 391 mid-range chainsaw improves fuel efficiency by up to 20% compared to previous models. The new air filtration system requires fewer filter changes, allowing for longer run times. Improved fuel efficiency and fewer filter changes save you time and money.

Print Spec Sheets
MS 391 Specifications
DISPLACEMENT 64.1 cc (3.9 cu. in.)
ENGINE POWER 3.3 kW (4.4 bhp)
POWERHEAD WEIGHT 6.2 kg (13.67 Ibs.)
FUEL CAPACITY 600 cc (20.3 oz.)
CHAIN OIL CAPACITY 350 cc (11.8 oz.)
OILOMATIC® CHAIN 3/8" RS3
GUIDE BAR LENGTHS* (Recommended ranges) 40 to 50 cm (16" to 20")
STIHL ROLLOMATIC®
POWER SOURCE Gas
STIHL recommends #3624 (33 RS3 72) OILOMATIC® saw chain and 20" 3003 008 8921 Ematic™ guide bar combination. The actual listed guide bar length can vary from the effective cutting length depending upon which powerhead it is installed.
Model Features
  • Zoom
    Reduced-Emission Engine Technology - Caring for Nature
    The STIHL Inc. “Caring for Nature” seal identifies its powered products that are more environmentally conscious, producing zero or low exhaust emissions. STIHL Inc. defines “low exhaust emissions” as being cleaner than EPA and/or CARB exhaust emission standards.

    More Information

Standard Features
  • Zoom
    Common Features for Chainsaws
    View the features common to many STIHL chainsaws.
  • Zoom
    Pre-Separation Air Filtration System
    This time-saving technology boosts the efficiency of the engine’s filter system, doubling the time between air filter cleanings. Air drawn into the engine is first separated via centrifugal force, ejecting the heavier dirt particles before being routed to the air filter. This pre-separation means less dirt to be captured by the air filter, resulting in less frequent cleaning and maintenance.

    More Information

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    Anti-Vibration System
    STIHL has developed a system for minimizing the vibration levels of handheld outdoor power equipment. The STIHL anti-vibration system helps reduce operator fatigue and provides a more comfortable working experience.
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    IntelliCarb™ Compensating Carburetor
    The IntelliCarb™ Compensating Carburetor is designed to automatically adjust the air/fuel ratio when the air filter becomes restricted or partially clogged and maintains the engine’s correct RPM. IntelliCarb™ uses air from the clean side of the air filter to control the diaphragm and flow of fuel. As the air filter becomes dirty and less air is available for the carburetor, the IntelliCarb™ system adjusts the fuel flow to compensate for the decrease in air flow. This is in contrast to typical carburetors that utilize this air from the “dirty” side of the air box.
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    Side-Access Chain Tensioner
    The side-access chain tensioner makes it much more convenient for the user to adjust the saw chain with a bar wrench as opposed to the typical location of the guide bar adjustment screw.
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    Toolless fuel and oil caps with retainers
    Simply lift the lever and twist the caps to remove or tighten. There‘s no need to use a tool to tighten or loosen.

Important Information
WARNING! The occurrence called “kickback” can cause serious or fatal injury. Always read the instruction manual carefully before using your saw. STIHL uses a green and yellow color-coding system to help you select a powerhead, bar and chain combination that complies with the kickback requirements of ANSI Standard B175.1 (gasoline-powered saws) and §30 of UL 1662/ ANSI Standard B175.1 (electric chainsaws). Ask your STIHL dealer about safe operating procedures and the advantages of the STIHL Quickstop® chain brake, STIHL Quickstop® Plus (Q) additional chain braking feature, STIHL reduced kickback bars and STIHL low-kickback saw chains.

STIHL recommends the use of green reduced kickback bars and green low kickback chains on all STIHL chainsaws.
* The actual listed guide bar length can vary from the effective cutting length based on which powerhead it is installed on.
Note: STIHL recommends use of fuel with no more than 10% Ethanol content. Using fuel with greater than 10% Ethanol content may cause damage to your equipment and may void your STIHL warranty. Learn More…
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.
Click to view the STIHL Limited Warranty Time Periods
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    •2.6 oz. bottle makes 1 gallon mix

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    Bar and Chain Oil
    STIHL Bar and Chain oil is formulated to adhere to the bar and chain, and to reduce wear. Special agents in the oil formulation help keep sap and pitch from clinging to the bar and chain.

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  • Complete Filing Kits Zoom
    Complete Filing Kits
    Kits available for the following chain types: STIHL PICCO Mini; 1/4" pitch chain; .325" pitch chain; 3/8" pitch chain; .404" pitch chain.
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    Chain Pitch File Diameter File Guide
    Part Number
    Sharpening Kit
    Part Number
    in. mm in. mm Part Number
    3/8 PMN 9.32 5/32 4.0 0811 411 8073

    5605 750 4327

    5605 007 1026

    1/4
    3/8 PM
    6.35
    9.32
    5/32 4.0 0811 411 8091

    5605 750 4327

    5605 007 1027

    0.325 8.25 3/16 4.8 0811 412 8088

    5605 750 4328

    5605 007 1028

    3/8 9.32 13/64 5.2 0814 243 3384 5605 750 4329

    5605 007 1029

    0.404 10.26 7/32 5.5 0811 412 8108 5605 750 4330

    5605 007 1030

For Your Safety
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    Performance Zip Chap

    The Performance Series Zip Chaps provide full wrap-around protection for a user’s lower leg area and are made to stand up to daily wear and tear. The outer material is crafted from durable orange Cordura® nylon fabric, an all-weather material used in a range of premium outerwear brands. Inside, the chaps feature six layers of Avertic® Pro by Engtex® cut retardant material, designed to reduce the risk or severity of injury in the event of contact with the rotating saw chain on a gasoline-powered chainsaw. For extra convenience, the chaps feature rows of zippers that run along the entire inseam of the chap, helping to ensure a comfortable fit that is easy to put on and/or remove. Visit our Dealership to see these chaps in person.

  • STIHL Pro Mark™ Dynamic Protective Gloves Zoom
    STIHL Pro Mark™ Dynamic Protective Gloves
    Durable and hardworking, STIHL Pro Mark™ Dynamic Gloves deliver professional-grade hand protection. The palm and inner fingers are made of full grain tanned leather, so you can work with comfort without sacrificing a firm hold. Featuring multiple layers of cut-retardant materials – Avertic® Pro and Dyneema fabrics by Engtex® – these gloves will help deliver protection without compromising the dexterity you need while operating a chainsaw. Accented with an orange rip-stop nylon backing, these dynamic gloves offer style and protection. Water repellant, breathable and featuring a Velcro wrist closure, STIHL Pro Mark™ Dynamic Gloves are as ready for the woods as you.
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Are You Ready for a STIHL?

MS 391 is rated 4.5 out of 5 by 240.
Rated 5 out of 5 by from Excellent saw in every way. Starts right-a-way every time, cuts fast and clean, well balanced, easy access for maintenance and cleaning. I mainly cut 16 to 24 inch pine logs and the saw cuts through quickly without bogging.I highly recommend the MS391.Mike
Date published: 2017-07-14
Rated 5 out of 5 by from INSANE POWER so I'm 12 years old and I ran this chainsaw for the first time more powerful than any Husqvarna I ran this thing is overpowered and excellent for what I need it for this is an insane saw it cuts fast I love it not even broken in yet and its still a champ.
Date published: 2017-07-13
Rated 5 out of 5 by from This makes retiring my old saw easy very pleased with my purchase Typical of all Stijl products they just run and so reliableMakes the work fun and quickOver all if you want a saw that you can pick up for a day of cutting or a hour or minutes get this saw as I find excuses to use it!
Date published: 2017-06-23
Rated 5 out of 5 by from Saw is a beast Put it to work for about 3 hours the first day. Cut through large trees like butter. Wish I would have bought a Stihl years ago.
Date published: 2017-06-16
Rated 2 out of 5 by from Unreliable Used this saw about 40 hours over two years before it quit starting. Starting it progressively got harder. Took to Stihl service center only to find out the ignition module is faulty. Bought one from Ebay and it still starts no easier. At least I have spark at the plug now but with arthritis I cannot pull it hard enough to start. I would think Stihl should last more than 40 hours before having to replace pricey parts.
Date published: 2017-06-08
Rated 4 out of 5 by from Quality built Product I am comparing this product to a 35 year old Pro Mac 700, so this may or may not be a fair comparison. A little disappointed in the power for a larger saw, had the 25" bar and chain installed at the dealer before purchase. Once its running, its a smooth cutting saw. Have run several tanks of gas thru it now, and am a little surprised at how finicky is is to start, especially after a warm refuel. Like the one quarter turn caps on the fuel tank and the oil tank, and the foot hole on the rear handle.
Date published: 2017-06-07
Rated 1 out of 5 by from Second day into owning this saw and it won't start Worked ok for about 3 hours yesterday, started every 4th or 5th pull but fought for an hour with it this morning thinking something must be wrong return to the dealer and they say it's gonna take 2 days to replace the carb on a saw that's 24 hours old absolutely pathetic , won't let me return it won't lend me a new one in reality I expected a complete replacement
Date published: 2017-05-31
Rated 1 out of 5 by from Brand new MS391, won't start. Bought a brand new MS391 to compliment my smaller Stihl saw, Got it home, read manual thoroughly & it would not start. Acted flooded, gave it a few hours, still wouldn't start, Checked plug, was dry. Convinced I had to be doing something wrong, I returned to my dealer the following day to get their opinion. Their resident technician was very cool, as we eliminated any mistakes I may have made. Fresh fuel? Check, Stihl premix. Choked properly? Check. He took cover off, determined it was flooded, although I hadn't attempted to start it that day. He tried to start it and had the same results I did, and determined it was a faulty carb. Very frustrating for a new saw, returned it, got my $$ back, Planned on using it this weekend to do a ton of tree work. Very dissimilar experience from other Stihl products I've bought.
Date published: 2017-05-29
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