Use bar-and-chain oil on the bar; gas saws run a 50:1 petrol-to-two-stroke-oil mix. Skip used motor oil and match winter or summer grades to temp.
Pick the right oil and your chainsaw runs cooler, cuts straighter, and lasts longer. Wrong oil turns into heat, galling, and stretch. This guide gives plain picks for the bar and for the engine, so you can pour with confidence and get back to cut.
Chainsaw Oil Types At A Glance
Every saw needs two kinds of lubrication. One protects the bar and chain. The other, on petrol two-stroke models, protects the engine. Battery and corded models use only bar oil. The table below lays out the matches.
| Saw Type | Oil You Need | Notes |
|---|---|---|
| Petrol two-stroke chainsaw | Bar-and-chain oil; plus petrol mixed with air-cooled two-stroke oil | Most brands run 50:1 mix; always check your manual |
| Battery chainsaw | Bar-and-chain oil only | No fuel mix; keep the bar oiler topped up |
| Corded electric chainsaw | Bar-and-chain oil only | Use an all-season or winter grade for cool weather starts |
| Pole saw (battery or corded) | Bar-and-chain oil only | Thin oil helps flow through long oil channels |
Choosing Oil For A Chainsaw: Bar And Engine
Bar-And-Chain Oil: What It Does
Bar oil clings to fast steel and keeps a thin film between the drive links and the rails. Tackifiers reduce fling, so oil rides around the nose and into the cut. An STIHL bar and chain oil or any quality all-season bar oil works on most jobs, with winter grades flowing better below freezing.
Good bar oil also guards the clutch cover, the rim or spur sprocket, and the drive sprocket on the powerhead. That thin film keeps pitch from baking on hot steel and makes cleanup faster at the end of the day. A steady feed also helps chain tension hold steady, since a lubricated chain grows less with heat. Watch your oil tank: on long cuts the level should fall near the same pace as the fuel. If the oil tank stays full while the fuel drops, the chain is running too dry.
Chain speed and bar length change the feed you need. A small homeowner saw with a 12-inch bar can run light feed in green wood. A pro saw swinging a 24-inch bar in oak needs a wide-open oiler and a thicker bar oil. Many bars include a small hole near the nose for a grease gun; clean that passage during routine care so the tip turns free.
Pick A Grade For The Weather
Oil gets thicker when cold and thinner when hot. In summer, a heavier bar oil stays on the chain at high chain speed. In winter, a thinner grade feeds faster and cuts drag on the oil pump. If your saw offers an oiler dial, open it up for dry hardwood and long bars, and back it off for softwood or short cuts.
Two-Stroke Mix For Petrol Saws
On the fuel side, fresh petrol helps as much as the right ratio. Old fuel turns gummy and can plug screens or jets. Buy in small amounts, mix what you plan to burn this month, and write the date on the can. If your saw sits between seasons, a sealed can of premix keeps starts easy and reduces varnish in tiny passages.
Two-stroke oil bottles list ratings and base stock types. Mineral oil blends cost less and work fine for light duty. Full synthetic blends handle heat and leave fewer deposits in long cuts or hot weather. Pick one brand and stick with it, so tuning stays consistent from can to can.
For modern pro and homeowner saws, a 50:1 petrol-to-oil ratio is the common spec. Husqvarna explains the math here: fuel-to-oil ratio of 50:1 means 2.5 fl oz of two-stroke oil per US gallon of petrol. Use fresh fuel, shake the can, top off the fuel, then fill the tank. If your manual calls for 40:1, use that.
Which Two-Stroke Oil?
Pick an air-cooled two-stroke oil that lists modern ratings and is sold for handheld tools. Avoid outboard TC-W3 oils; those are blended for water-cooled engines. A full synthetic keeps ports cleaner, but any quality bottle that meets the maker spec and is mixed at the right ratio will keep the engine happy.
What Not To Use And Why
Skip used motor oil. Particles and acids chew up pumps and bars, and the dark mist coats soil and water around the worksite. Fresh motor oil also slings off fast and lacks the sticky additives that bar oils use. If you need a cleaner footprint near streams or parks, try a rapeseed-based option. The rapeseed-based biodegradable bar oil noted by the U.S. Forest Service reduces toxic load and still protects the bar.
Substitutes In A Pinch
What about ATF, diesel, or cooking oil? ATF is thin and full of friction modifiers built for gearboxes, not chains. Diesel is a solvent and lacks lubricity. Kitchen oils lack the sticky agents that keep a film on fast chain, and they turn to gum in storage. Plant-based bar oils sold for chainsaws are a different product altogether: they use seed oils plus tackifiers and pass cold-flow tests. If you want a low-odor shop, that’s the route that delivers smooth cuts without the haze.
Used motor oil deserves a second mention. It carries metal bits, fuel dilution, and acid from long drain intervals. That mix eats pumps and rails and stains wood and paving. Drop it at a proper collection point and feed your saw the right stuff.
Best Oil To Use For A Chainsaw In Cold Weather
Cold mornings thicken oil and slow the feed. When the chain looks dry or the cut smokes, move to a winter grade or a lighter all-season oil. On some Oregon bars, the service manual even allows thinning bar oil with a small share of kerosene or diesel for extreme cold; that’s a niche fix and only for deep frost jobs. For most users, a bottle labeled “winter” solves the feed problem without mixing.
Quick Checks Before You Cut
- Fill both tanks. Bar lube should drop at a rate similar to fuel on long cuts.
- Point the bar at a clean board and rev for a few seconds. A light line of oil should appear.
- Crack the oiler dial open one step at a time until the chain shows a wet sheen after a cut.
Bar Length And Wood Type Matter
Long bars and dry hardwood raise heat. Use more feed and a heavier oil on hot days. Short bars in softwood can run on a lighter feed. Watch your chips: dry, dusty chips hint at poor oiling or a dull chain.
Setup, Checks, And Flow Tuning
Fit the right oil, then make sure it gets where it needs to go. Clean the oil port, the bar groove, and the sprocket nose. Flip the bar each sharpening to even wear. If the chain turns blue or grabs, stop and sort the oiling before the next pass.
How To Test Oiling On Wood
Start a waist-high cut into scrap hardwood. Pause. Touch the chain with a gloved finger. It should feel wet, not sticky-dry. If the chain is dry, open the oiler or move to a thinner grade. If the side casing and muffler side drip after each cut, dial the feed back a notch.
Mixing Fuel Without Guesswork
Cleaning takes minutes and saves money. Pop the side casing, pull the bar and chain, and scrape the groove with a thin bar-groove tool. Poke the oil hole clear. Spin the tip to feel for rough spots. If the tip binds, add a shot from a small grease gun and wipe away the excess. Reassemble, set the tension with the chain warm, and make a short test cut. If the cut wanders, sharpen the chain and check the oiler again before blaming the bar.
Bad oiling leaves clues. Blue marks near the nose, chatter on the rails, a burnt smell from the casing, or chrome flaking off the drivers all point to poor feed. Fix the cause and the saw will run cooler and straighter.
Use one can for mix and label it. Add half a can of petrol, measure the oil, pour it in, top off the fuel, and shake. Store the mix in a tight can and rotate stock often. Premixed sealed fuel is a tidy option for saws that sit between jobs.
Quick 50:1 Mix Chart
Use this chart to measure two-stroke oil for common fuel amounts. It matches the 50:1 ratio used by many current saws.
| Fuel Volume | Oil (Metric) | Oil (US) |
|---|---|---|
| 1 litre | 20 ml | 0.68 fl oz |
| 5 litres | 100 ml | 3.4 fl oz |
| 10 litres | 200 ml | 6.8 fl oz |
| 1 US gallon | 50 ml | 2.6 fl oz |
| 2 US gallons | 100 ml | 5.1 fl oz |
| 2.5 US gallons | 125 ml | 6.4 fl oz |
Bio Bar Oils And Site Rules
Some crews and parks ask for oils that break down fast in soil and water. Plant-based bar oils built from canola fit that brief and cut smell around the sawyer. They cost more than mineral oil, yet many users like the tradeoff during tree care near lawns, patios, or water.
When To Switch To Bio
Reaching over a garden bed? Working over stonework or a deck? That’s a solid time to run a plant-based blend. Keep an extra bottle in the kit so you can swap when the job calls for it.
Electric Saws: Oil Picks And Tips
Electric saws shine for yard work and indoor cutting, like trimming beams in new builds or sizing lumber in a garage. For those jobs, clean-running bar oil keeps dust down and the workspace tidy. A thinner grade helps tiny pumps feed well at lower chain speeds. Many battery saws also pause the oiler between cuts; if the chain runs dry after several short starts, hold the trigger a second longer at the end of a cut to give the pump time to push oil forward.
Storage And Shelf Life
Seal caps tight, keep bottles upright, and stash them out of sun. Two-stroke mix ages, so make small batches. If a can smells sour or the saw gets hard to start, pour a fresh batch, clean the screen, and try again.
Simple Troubleshooting
- New chain runs dry: clean the bar oil holes and groove.
- Fresh mix, hard start: spark plug fouled or fuel aged.
- Oiler maxed, still dry: try a thinner grade or service the pump.