The 390 XP is not a weekend warrior tool. It is a dedicated professional felling saw designed for the heaviest duties in the woods. While the industry shifts toward computerized carburetors, the 390 XP stands as one of the last great analog titans—a saw for people who know how to read a spark plug and value mechanical reliability.
The Competitive Landscape
| Model | Displacement | Power Output | Weight | Best Use Case |
|---|---|---|---|---|
| Husqvarna 390 XP | 88.0 cc | 6.44 hp | 15.6 lbs | Professional Felling / Milling |
| Stihl MS 391 | 64.1 cc | 4.4 hp | 13.7 lbs | Farm & Ranch |
| Husqvarna 455 Rancher | 55.5 cc | 3.5 hp | 13.2 lbs | Landowner |
| Echo CS-590 | 59.8 cc | 3.9 hp | 13.2 lbs | Value Prosumer |
Technical Engineering Deep-Dive
The 390 XP features a high-pressure die-cast magnesium crankcase. This is not just about durability—magnesium sheds heat faster than aluminum or composite, preventing heat soak during extended cuts. Inside sits a forged three-piece crankshaft capable of 2,000+ hours within factory tolerances.
The centrifugal Air Injection system flings larger dust particles away before they reach the filter. In practice, this means a full week of felling without needing to blow out the HD filter. Our key advice: The 390 XP uses a traditional Walbro carb with adjustable H and L screws. This tunability is why many pros prefer it over newer electronic models—you can adjust for altitude changes with a small screwdriver.
For more on power source decisions, see gas vs electric chainsaw.
Real-World Performance
Running a 28-inch bar with square-ground chain on frozen Sugar Maple, the 390 XP does not just cut—it eviscerates. The 4.8 kW output keeps chain speed high even under heavy downward pressure. For bore cutting, the center of gravity is low and well-balanced.
For chainsaw milling, the 390 XP is the starting point. The high-output adjustable oiler keeps long bars lubricated through the grueling process of ripping slabs.
Ergonomics & Operator Comfort
The LowVib steel-spring system isolates the engine from the handles effectively. After a six-hour bucking shift, hands do not have the pins-and-needles sensation typical of vintage pro saws. At 15.6 lbs dry, this is a heavy saw—you will feel every ounce by late afternoon. Key advice: Do not limb with this saw. Use a dedicated 40-50cc climbing or limbing saw for overhead work.
Chainsaw Safety
Review our chainsaw safety guide before operating. A 90cc saw generates extreme kickback forces. Always use the inertia brake, wear full protective equipment, and never cut alone.
Maintenance & Serviceability
Fuel quality is critical. Never run 87-octane ethanol fuel—the heat of an 88cc engine will cause ethanol to separate and lean out, scoring pistons. Use 91+ octane ethanol-free fuel. The adjustable oiler must be cranked to maximum when running 32-inch bars. Check the spark plug gap regularly—high-output ignition systems make gapping critical.
Always verify your bar and chain match your model.
Hardware Specifications
- Displacement: 88.0 cm³
- Power Output: 4.8 kW / 6.44 hp at 9,600 RPM
- Idle Speed: 2,700 RPM
- Torque, Max: 4.7 Nm
- Weight: 15.65 lbs
- Fuel Tank: 0.9 Liters
- Oil Tank: 0.5 Liters
- Sound Power: 119 dB(A)
Pros & Cons
Pros: Massive torque for largest logs; no electronics to fail; best-in-class Air Injection filtration; magnesium crankcase lasts a lifetime; versatile for felling and milling.
Cons: Heavy for long days; high fuel consumption; air filter cover clips feel flimsy; requires strong arm to start even with decompression valve.
Final Verdict
The Husqvarna 390 XP offers a blend of raw power and mechanical simplicity increasingly hard to find. If you are dropping 36-inch hardwoods or running a mill, this is the undisputed king of the 90cc class. It rewards skill and punishes laziness.
SAWOFF Rating: 4.8 / 5
Get out there and cut. Safely.
Frequently Asked Questions
What is the largest bar I can run on a Husqvarna 390 XP?
Factory recommends up to 28-32 inches. The 390 XP has the oiling capacity and torque to pull a 36-inch bar in most hardwoods. For milling softwoods, some users push to 42 inches with skip-tooth chain.
Does the 390 XP have AutoTune?
No. It uses a traditional manually adjustable Walbro carburetor. If you want AutoTune in a similar power class, look at the Husqvarna 592 XP.
What fuel-to-oil ratio should I use?
Husqvarna recommends 50:1 using XP synthetic 2-cycle oil. Stick to 50:1 with ethanol-free gas to ensure piston ring longevity under extreme heat.
Why is the 390 XP so hard to start?
It is a high-compression 88cc engine. Ensure the decompression valve is fully engaged before every pull. If flooded, remove the spark plug and clear the cylinder.
How does the 390 XP compare to the Stihl MS 661?
The MS 661 is 91cc with M-Tronic. The 390 XP is often considered smoother due to LowVib springs, while the Stihl has a more aggressive feel. Many pros choose Husqvarna for ergonomics.
Can I use this saw for firewood?
You can, but it is overkill for firewood under 24 inches. For manageable firewood processing, the Husqvarna 460 Rancher is a better fit.
Why is my saw four-stroking at full throttle?
This is normal. When not under load, the carb tune causes it to four-stroke slightly as a safety feature to prevent leaning out. Once in the cut, it cleans up.
