Stihl MS 391 Review: Is it worth buying in 2024?

When you look for a reliable chainsaw for farm or ranch work, you would typically consider the Stihl MS 271, aka farm boss. Its title would lead you to assume its reliability to this specific function. But did you know there are other models with the same name? Stihl 391 is also known as the farm boss.

The MS391 is a powerful chainsaw that has a lot to offer. Unfortunately, this machine is not getting what it deserves regarding reviews. With a powerful engine and high engine power, this chainsaw will take your cutting tasks to a new level.

If you want to know more about the Stihl MS 391 review, keep reading this blog post. We will give you a detailed review that covers everything related to its performance, features, and user experience. So, read on!

Stihl MS 391 Review

Table of Contents

This Farm Boss model comes with a large displacement and increased horsepower. It is also compatible with various bars to accommodate different cutting needs. When you look at its key features, you might think it is a professional chainsaw.

However, it is not a professional saw. Still, it is not a beginner saw either. It is suitable for heavy-duty projects commonly found around a ranch or farm.

Now it is time to get an in-depth look into the features and performance of the Stihl MS391.

Construction Quality & Material

As a non-pro saw, the machine is mainly built of polycarbonate, aka reinforced polymer. This is a high-quality and durable plastic. 

Typically, this is less durable than the metal casing, particularly the magnesium casing of the pro-level chainsaws. However, it contributes to this farm boss’s lightweight and relative affordability.


The features of this MS prove its ability to be an all-purpose chainsaw that suits farm work. It also comes with decent torque without adding any physical burden to the operator. It has advanced Stihl features, including fuel efficiency, low emissions, and an additional chain braking feature.

1. Engine Capacity 

This chainsaw comes with a big engine with a displacement of 64.1 cc. This number makes this Farm Boss model the most significant engine of all other saws with that same name. So, it is way more powerful than the well-famed Stihl MS271 farm boss.

2. Engine Power

This factor is essential in judging the performance of any chainsaw. It is not just about the engine’s displacement but also about its horsepower. The higher the value the engine offers, the better performance you will get. In our case, the Stihl MS391 provides 4.4 bhp. This number makes it the highest version among all the other farm bosses.

3. Powerhead Weight 

The weight of a chainsaw determines its maneuverability. Generally, pro users won’t mind a slightly heavy chainsaw, but average users always seek a lightweight one.

The dry weight of Stihl MS391 is 6.2 kilograms ( 13.6 pounds). With the addition of fluids and accessories, its overall weight can reach 6.5 kilograms.

4. Compatible Bars 

Like many other chainsaws in the 300 series, this one is compatible with a wide range of bars. It works just fine with short and long guide bars. The recommended length for optimal power is 20 inches. However, this chainsaw will work well with any bar between 16 and 24 inches.

5. Power Source 

This chainsaw runs on gas. It also uses a fuel ratio of 50:1. This saw is similar to many other saws from the same manufacturer. The vast majority, if not all, of Stihl chainsaws, use 50:1 ready-mixed fuel. 

6. Fuel Tank Capacity 

The larger a fuel tank is, the more comfortable you will be. In this farm boss model, you will find a large tank that holds larger quantities of recommended fuel compared to all farm boss models. The Stihl MS391 has a tank capacity of 20.3 ounces of the right gasoline type.

7. Chain Oil Tank Volume

A large oil tank also gives you extra peace of mind. It will spare you the concern about frequent tank refills. This MS 391 comes with an oil tank with a capacity of 11.8 ounces.

When this relatively large tank is combined with the emetic lubrication system, this saw will save up to 50% of its oil capacity. This feature allows for adequate bar oil consumption.

8. Anti-vibration System

This is an advanced feature that is common in many Stihl saws. This system aims at reducing the feeling of intense vibration in your hands while operating the Stihl MS362. The presence of a collection of springs achieves this feature.

These springs isolate the handles of power tools from the engine and chain. This way, the engine’s and chain’s vibrations won’t be excessively felt in your hands. Eventually, you will feel less fatigue from holding the saw for hours.

9. Reduced Emissions 

The advanced low-emission engine technology is part of Stihl’s caring for nature policy. This chainsaw is labeled with a “caring for nature” seal. This indicates that the saw releases low to zero exhaust. This means that the emissions from this chainsaw are cleaner than EPA emission standards.

10. Advanced Air Filter

The air filter is essential for keeping the engine clean and debris-free. But the advanced pre-separation air filtration in the Stihl MS391 takes the filter function to a new level.

The advanced system entirely separates larger debris or dirt particles from tiny ones in the early stages. This way, there would be no large particles reaching and blocking the filter in the first place.

Typically, this feature will give you a long time between air filter washings. Reducing the frequency of air filter cleanings will make you more comfortable.

11. Better Access to the Chain Tensioner

Adjusting the chain is a mandatory task to ensure efficient cutting and safety. But the whole scenario of loosening the bar nuts and removing the side panel can be daunting. With the Stihl MS391, you will have access to a side tensioner. You can find it right under the sprocket cover. So, there is no hassle or tools needed for that.

12. Automatic Carb Adjustments

This advanced feature is way different from the traditional carbs on older models. The IntelliCarb Compensating Carburetor technology allows for automatic adjustment of the carburetor. This way, the correct and required air and fuel levels will keep flowing into the carburetor for starting and running the machine.

Moreover, a clogged air filter won’t get in the way of this carburetor. This engine component will keep drawing the necessary quantities of air from the unclogged side of the filter. 


Stihl ms391 comes with a power-to-weight ratio of 1.9 kg/kW. This is one of the most obvious drawbacks of this machine. Many other similar saws have the same displacement but offer a higher ratio. The Stihl MS362 is just one example of these similar saws.

That said, this chainsaw still belongs to a big brand. This means it is designed to perform at its best and last for years. If you want optimal performance from this saw, match it with a long bar of at least 20 inches. Also, get a complete chisel chain to increase the cutting efficiency.

Stihl MS 391 Reviews: What do people say? 

There is no consensus about Stihl ms391. While many users are happy with what they got, others are utterly dissatisfied with the saw. On Stihl’s website, the saw got a rating of 4.3 with nearly 750 reviews. This indicates a larger number of sales.

User Feedback

In general, users are happy with the smooth operation of this saw. They do not face issues related to starting or bogging down. The presence of a single combi lever helps them start or stop the engine as they wish. It also gives them better control of the choke and throttle.

Also, many real-life users praise the machine’s quality and durability. Many of them have been using the same saw for around 10 years. They liked that they did not have to replace many parts. According to their experiences, they had only to change a filter and a spark plug after a long running time.

Meanwhile, users disliked the heavy weight of this saw. So, the average user can only carry it around for a short time. So for them, it lacks the portability feature found in similar chainsaws.

Another point that many users are not happy with is the value for money. This saw is costly. There are some other better options in a lower-price category. But after all, a major brand like Stihl is not expected to produce a cheap, powerful saw.

Product Satisfaction 

With countless sales in various parts of the world, the Stihl MS391 has created some debate. Users are swearing at it, while others consider giving up the whole brand based on their experience with this machine.

Satisfied clients do not find its drawbacks disturbing, as they are not frequent users. So, the machine is powerful, fast, and reliable for an occasional user. There is no need to mention that it is built to last.

Unhappy clients expected more for the prices they paid. Some of them wanted a decompression valve. Others sought more advanced safety features to reduce the chances of dealing with kickback chains.

Customer Service

Buying from a trustworthy and licensed Stihl dealer spares you many troubles. A decent dealer would honor the warranty and get you the spare parts you want.

In general, Stihl provides a form for complaints on their website if you encounter after-sales-related issues. Also, you can find more details on their site for contacting customer service.

If you want to replace your current MS391, you must return it within 7 days after purchase. The machine should be in its original shape. Remember that you can enjoy warranty coverage for this Stihl farm boss for 2 years.

This warranty is valid as long as your machine is used for domestic purposes. However, professional uses of this power tool are only covered by one year warranty.

Should You buy the Stihl MS 391? 

This farm boss model is a good choice for rare light to medium forestry tasks. As a domestic user, you will love this saw. But things are different for pro users; they won’t be 100% happy with the performance. It comes with a low power-to-weight ratio.

This high-powered chainsaw has a lot of potentials that is challenged by its weight. If you are willing to let go of the ultimate maneuverability feature, you might not experience a lot of issues with this saw.

However, you can get better options from the same premium brand for that amount of money. With a long bar, you can get this saw for around $750, depending on the dealer and other accessories. 

You can have better options in terms of portability without giving up plenty of power. Your options include Sithl MS 271, Farm Boss, and Sithl MS 261.

The Stihl MS391 is powerful outdoor power equipment with a large engine and many great features. It is not capable of performing frequent, large-scale cutting projects. So, it is a mid-range chainsaw that has an engine with a large capacity. Despite its good performance, it is considered a bit overpriced for its abilities.

5/5 - (7 votes)
( Licensed Chainsaw Professional )

Jake is a chainsaws expert with a wealth of knowledge and experience in the field. He is a licensed professional by the National Chainsaw Program, which attests to his skills and expertise in the safe and efficient use of chainsaws.