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What Motor Oil is Best for Winter? (And Other Cold-Weather Questions)

The Best Winter Motor and Transmission Oil Choice

Synthetic oil is best for winter.

We’re done here.

If only it were that simple. But most people want empirical data to support such claims.

Well, take a look at the video. We cooled a conventional 5W-30 motor oil and AMSOIL Signature Series 5W-30 Synthetic Motor Oil to -40º. As you can see, the conventional oil thickened so much that it barely flowed from the beaker. The AMSOIL product, on the other hand, flows almost immediately.

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Why the dramatic performance difference? In answering that question, I’ll also answer the question hoss61761 poses on social media:

Conventional oils contain waxes that solidify when the temperature drops. This severely impairs the oil’s ability to flow when you crank your engine. In some cases, the oil can thicken so much that it prevents the crankshaft from spinning fast enough to start the engine.

Prior to using AMSOIL, I had a Cutlass Ciera that was notorious for refusing to start on our cold Minnesota mornings. The dirt-cheap big-box-retailer oil I used back then thickened so much the engine would barely turn over.

Why synthetics flow better in winter weather

Synthetics, in contrast, don’t contain waxes due to the chemical-reaction process used to construct synthetic base oils. As a result, synthetics demonstrate far better cold-flow properties than conventional oil. Not only will your vehicle start more easily (I’ve yet to have one of my vehicles using AMSOIL fail to start, even with temps pushing -30ºF), the oil will flow more quickly, ensuring oil reaches vital components faster. This, in turn, maximizes wear protection, helping your engine last longer.

Check the oil’s pour point

If you want more data to prove synthetics’ cold-weather superiority, check the oil’s Product Data Sheet. Look for the oil’s pour point. Lower numbers indicate better cold-flow, thus better cold-weather performance.

In the example here, you can see that AMSOIL Signature Series 5W-30, the same oil shown in the video above, has a pour point of -58ºF (-50ºC).

What is cold?

Not to get existential here, but it’s a relevant question. Folks in the south whose idea of winter is putting shoes on for a couple weeks in January may think they’re off the hook. Do they need to waste mental energy on motor oil cold-flow properties?

Good cold-flow is important to Southerners, too. Here’s why.

Engineers agree that most engine wear occurs during cold starts. There are several reasons, but two concern us for this discussion:

  • Gravity causes much of the oil to fall back into the oil sump, leaving components unprotected
  • Cold oil doesn’t flow immediately at startup, temporarily starving the engine of oil

While true that oil thickens more in sub-zero winter weather and causes increased starting difficulty, an engine is considered “cold” after it’s sat long enough to cool to ambient temperature, typically overnight.

The oil inside your engine cools as it sits overnight. As it cools, its viscosity increases (it thickens). When it’s time to start your vehicle in the morning, the thicker oil doesn’t flow through the engine as readily as it does when it’s at operating temperature. It’s during this time that vital engine parts can operate without lubrication, increasing wear. So, even in warm climates, cold-start wear is a problem. Southerners are well-advised to use a good synthetic oil with excellent cold-flow properties, too.

Thick or thin oil in winter?

Motorists sometimes ask if they should use thicker or thinner oil in the winter. Fortunately for them, we wrote a whole post on that topic. Check it out here.

Should I Switch to a Lighter Viscosity Oil in Winter?

To summarize, use the lowest viscosity oil your vehicle manufacturer recommends in the winter. Most automakers recommend a lone viscosity year-round. But some allow you to switch to a lower viscosity in winter, which helps improve cold-flow.

If your owner’s manual says you can switch to a lower viscosity oil in winter, go for it.

Shift to better winter protection

While I have you here, I should talk about transmission fluid, too. Like motor oil, it thickens in cold weather. The cold, thick fluid doesn’t flow readily through the intricate network of passageways in the transmission valve body or through the small solenoid openings. What does that mean to you?

  • Delayed shifts
  • Elongated shifts
  • Hard/harsh shifts
  • Reduced wear protection

Cold, thick transmission fluid doesn’t flow readily through narrow valve-body passages, leading to poor shift quality.

Again, I’ll go to the well of personal experience. After buying a Honda CR-V several years ago, I switched to AMSOIL synthetic motor oil…but I neglected to change the transmission fluid. Fast-forward to winter and one of our trademark -20ºF mornings with a wind chill pushing past -40º. The Honda started, but she shifted slowly and with much wailing and gnashing of teeth. The entire vehicle shuddered as it reluctantly found second gear heading down the road.

Switching to synthetic transmission fluid solved the problem. The fluid flows much more readily in the cold, which translates into smoother shifts. It also means the gears and bearing are receiving vital lubrication, too. Anyone who’s shelled out thousands of dollars for a tranny replacement knows how important that is.

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Bottom Line: Synthetic motor oil and drivetrain lubricants perform better in the cold than conventional oils. They flow better for easier starts, smoother shifts and better protection against wear. Upgrade to synthetics to maximize cold-weather protection and performance.

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What to Know When Choosing a Fork Oil

When is the last time you changed shock oil?

Fork Oil – Which do I use?

We sell a good amount of fork oil in Sioux Falls thanks to some great motorcycle shops who know how to maintain the various units out there. But if you have a shop manual, the right tools and some patience give it a try!  Some units are very simple, quick and easy.

A fork oil’s number-one task is to deliver consistency. Consistent dampening despite temperature changes. Consistent rebounds despite different terrain. Consistent performance so you can ride or drive confidently.

Consistency.

What fluid would provide the best shock consistency?

Water.

Yes, water. But you don’t want to use it in your shocks for reasons you can probably guess, but we’ll get to that in a bit.

What shocks do

The shocks on your dirt bike, race car, ATV or other vehicle absorb abnormalities in the terrain and help stabilize the ride. They also absorb impact when landing a jump, taking some of the beating off the vehicle and your body. And they “load up” with energy when approaching a jump, helping you fly over whatever’s in your way.

The shock uses fluid to control dampening and rebound.

Say you’re riding your dirt bike and land a jump. The force depresses a piston inside the shock that pushes fork oil through calibrated valves. The fluid’s rate of flow through the valves influences the amount of dampening and rebound.

A thin fluid flows faster and results in quicker, springier shock feel. In contrast, a thick fluid flows more slowly and results in slower rebound and stiffer shock feel.

Fork oil viscosity matters

The fluid’s viscosity (often thought of as its thickness) influences how fast or slow the oil flows through the shock valves. If you prefer quick rebounds, use a lighter fluid. If you like slower rebounds, use a heavier fluid.

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Easy, right?

Sure, if the viscosity of the shock oil never changes.

However, cold ambient temperatures increase the oil’s viscosity, resulting in slower rebounds. Then, after you’ve made a few laps and the vehicle’s heated up, the fork oil thins as it warms. That’s because fluids become thinner when they warm up. Think of molasses or honey. The warmer oil flows faster through the shock valves, leading to inconsistent shock feel.

H2O, no

That’s why water theoretically would provide the most consistent shock feel. Its viscosity doesn’t change between 33ºF (0ºC) and 211ºF (100ºC).

On a cold morning, after a long ride or on a blazing-hot day, water maintains the same viscosity provided it doesn’t freeze or boil. When was the last time you had a thin or thick glass of water? Hence, it would flow at the same rate through the shock valves, resulting in consistent feel.

Much more than flow, though

But the fork oil must do more than influence rebound and ride feel. It also must protect against wear and corrosion, two tasks at which water is notoriously bad.

The shock oil has to protect the shock tubes, seals and valves from wear as they constantly rub together. Minus good wear protection, the shock would tear itself apart in short order. Plus, the oil must form a layer on parts to prevent formation of corrosion. If corrosion starts, it won’t stop, spreading and depositing flakes of contaminant in the oil that act like sandpaper and scour metal parts until they’re worn out.

Look for a high-VI fork oil

Instead, look for a fork oil with a high viscosity index (VI). A higher VI indicates better resistance to viscosity changes throughout broad temperature swings. That translates into consistent shock performance and feel despite the ambient and operating conditions. And a consistent ride equals a more effective rider.

Points to consider when looking for fork oil

1) No standard viscosity

Your engine manufacturer recommends a specific viscosity of motor oil for best protection and performance. In the world of shocks, there are no universal viscosity requirements or recommendations. Each shock oil manufacturer is free to formulate its oils to whatever viscosity it deems appropriate. That means one brand’s “light” fluid could behave like another brand’s “medium” fluid, and so on.

2) Once you find a shock oil you like, stick with it

For the reasons listed above, avoid switching between fluids if you can. Once you have the proper suspension set-up for your body weight and riding style, stick with it. The shock oil is one of the biggest variables in your suspension tune, and messing with it can throw off suspension feel and your riding confidence.

3) Look at viscosity at 40ºC

If you decide to switch shock oil, compare the viscosity of the fluid you’re currently using at 40ºC to the same data for the new fluid. The closer the results, the more similar the oils will perform. Reputable manufacturers publish product data bulletins for their shock oils and post them online. If you can’t find a data sheet for the oil you’re considering, think twice before using it.

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How to Clean a Gun for Hunting Season

gun barrels image

How to Clean a Gun for Hunting Season

Fall is fast approaching, which means if you’re an avid hunter, you’ve already been out kicking the bush testing your skills. Because I work during the week, I suppose I can be considered a weekend warrior – not too uncommon among us hunting kind.

That said, you never can plan great weather on the weekends, so we play the hand we’re dealt. At times, depending on what I’m chasing, bad weather is music to my ears. No matter what you are up to or when you do it, there is one thing I can promise: a successful hunt begins with a properly operating gun.


Don’t make the mistake of neglecting your most useful tool, as I did a few years ago on a goose hunt in Iceland, which left me frustrated and cussing. Two things will undoubtedly happen at the worst time: click and no bang, or the security you thought you had in that second or third shot of your semi-auto vanishes, leaving you with a single-banger.

Not good when the geese are coming in droves.

Fortunately, I corrected my faulty actions in Iceland simply by cleaning my shotgun. Yes, it was as simple as that, and I was back up and firing dependably.

Hunting is supposed to be relaxing and fun – don’t make it stressful. Clean your gun! Keep reading and I’ll give you a few tips on the cleaning process.

How to clean a gun

Like I’ve said in the past, I’m not a professional hunter or gunsmith. I’m just an everyday guy who likes to pull the trigger. So, my methods are my methods, which may not be your methods. Everyone is different. We all may use different rods, patches, rags, solvents, lubes, etc. In the end, however, what I strive for is a clean, dependable firearm. Probably not too far off from what you hope for in your firearm.

The following tips are based on personal success, not the success or methods of others. While we all have opinions, I think we can all agree that your firearm will be happier if you clean it using this process.

1) Make sure your gun is unloaded

The first and most critical step. People die every year cleaning a gun they thought was unloaded. Don’t be that person. Double check and make sure the chamber is empty. If the gun holds extra rounds, remove them.

2) Have all the tools you need available

I recommend the following:

I’m a little biased toward the cleaner and lubricant I use since I helped develop these products and I know they work. You may choose another brand and like it. That’s great; but think about giving these two products a try. You won’t be disappointed.

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3) Disassemble your gun

Now that we have all the tools we need, let’s get down to business.

I like to completely disassemble my guns. Sure, if I’m in a rush, I’ll leave them together, but to really clean a gun inside and out, you have to take it apart. Reference your user’s manual since it typically provides instructions on disassembly for cleaning. If you are unsure or worried about putting it back together correctly, leave it assembled.

4) Clean the barrel

I start with the barrel. Spray the inside with solvent. Let the solvent soften the residue and wash it out the end of the barrel.

Then, attach a clean rag to your cleaning rod and run it down the barrel a few times. The rag will help remove residue. Look down the barrel and see if it is shiny and smooth. If you haven’t shot much, it may require minimal cleaning. But, often you have to work a little harder to clean it.

Take the dirty rag off the cleaning rod and attach the bore brush. Spray the inside of the barrel again and run the bore brush through the barrel a few times. Remove the bore brush from the cleaning rod and run another rag through the barrel.

Look down the barrel again. It should be smooth and shiny. If not, repeat this process until clean or until you can run a rag through the barrel and have it come out clean. Once the inside of the barrel is clean, run a clean rag dampened with lubricant down the barrel. I use AMSOIL Synthetic Firearm Lubricant and Protectant. This leaves a thin film on the inside of the barrel as protection against corrosion.

The picture on the left shows a shotgun barrel after firing 100 rounds. The picture on the right shows the same shotgun barrel after being cleaned with AMSOIL Firearm Cleaner.

5) Clean the action

Depending on your gun, the action may include several moving parts, and they’re often coated with powder residue. This area is the source of most misfires or jamming issues.

Clean each component of the gun’s action with the same solvent used to clean the barrel. Use a clean rag soaked in solvent to wipe each component clean.

Once clean, dampen another clean rag with lubricant and wipe each action component. The lubricant in this area does multiple jobs. It protects from corrosion and provides the necessary lubrication the action components need as they slide against one another. Without lubricant here, the firearm is exposed to wear, reducing its life and dependability.

AMSOIL Specializes in the one aspect no other addresses: Rust protection beyond expectations. That goes for our classic car formulations and antifreeze.

6) Reassemble the gun and lubricate external surfaces

Wipe the outside of the firearm with a clean rag dampened with solvent to remove any powder residue, dirt or oil left by your hands. Once clean, take another clean rag dampened with lubricant and wipe all the surfaces. This helps protect the external surfaces from corrosion.

This process is not all-encompassing. It’s possible your user’s manual provides additional cleaning recommendations. Either way you slice it, your gun should be clean, well-lubricated and more dependable than it was before your cleaning process.

I can’t take responsibility for issues resulting in the improper reassembly of your firearm. Like I said, it’s best to know how to put it back together before you take it apart. Or, call your local gunsmith and he’d be happy to help.

Remember, hunting is about reducing stress and coming home with your day’s limit. Don’t let a dirty gun get in the way of that effort. Best of luck hunting this season. Be safe.

Product available in Sioux Falls at Stan Houston’s and the AMSOIL location at the Tea Exit.

Steps To Maintain Your Snowblower – Things to Know

check belts from idle wear in the spring on snowblowers

Never Overlook This When Maintaining Your Snowblower

Thanksgiving day, 2016. While my family was gathered in my dining room, imbibing spirits and making merry, I was in the shed disassembling the carburetor on my snowblower, reeking of petroleum as rivers of gasoline flowed under my jacket cuffs and saturated me to the elbows.

Here’s what happened, and here’s how to avoid it.

Snowblower maintenance can be distilled to this Golden Rule: Maintain your fuel system.

I’ll say it again: Maintain your fuel system.

A snowblower that won’t start is almost always due to a fuel problem. And nothing raises your blood pressure like a dead snowblower following the season’s first snowstorm. You know it! We always wait to the last minute on that first snow.

Preventing fuel-system problems starts in the spring prior to storage.

Leave the carburetor full of gas

This is where everything unraveled for me. One theory says that shutting off the fuel line and running the engine until the carburetor empties helps prevent varnish that plugs the jets and prevents starting.

Wrong, at least in my case. As I discovered, leaving the carburetor empty and exposed to air hastens oxidation and varnish. Fluctuating temperatures and humidity throughout the summer invite varnish, and it doesn’t take much to plug the tiny orifices in a carburetor. Then, it’s just a matter of time before you’re stinking of gasoline on Thanksgiving day while blasting carb cleaner on everything within reach.

Instead, add fuel stabilizer at the end of the season, run the engine for a few minutes to distribute the treated gas throughout the system, then shut down the engine. Now you can shut off the fuel line for the summer. The treated fuel in the carburetor bowl provides protection and helps keep components clean.

Some people claim you should run the carburetor empty since the gas will evaporate anyway. That may be true, but evaporation takes time, and the carburetor will at least be protected in the interim.

Stabilize the gas

As mentioned, treat gas with stabilizer prior to storage. Stabilized fuel protects against oxidation and varnish throughout the summer.

Use ethanol-free gas

When water infiltrates your gas tank in the form of melted snow, it can cause phase separation, a phenomenon that occurs when the bond between ethanol (present in most gasoline sold today) and gasoline breaks. When this ethanol/water mixture enters the combustion chamber, it creates a lean-burn situation that can damage your engine.

For best performance, use 91-octane, non-oxygenated (ethanol-free) gas. Many gas stations offer non-oxygenated gas and advertise it for powersports and off-road use. It’s a little more expensive, but spending a few extra dollars a winter to help your $1,000 dollar machine run strong isn’t a factor, in my opinion. At the very least, use ethanol-free gas during storage to help ward off phase separation.

Perhaps test your gas to see if it is really and truly ethanol free. I know many who say “I never use ethanol” and after testing the source gasoline it turned out to be laced with ethanol! Put your gas in a glass jar and see if you see it separate over time. Sometime you need to shake it up.

(Find out how to fight ethanol problems in small engines.)

If you use ethanol-blended gas, consider continuous use of a fuel additive, such as AMSOIL Quickshot, formulated to address ethanol-related performance issues.

Change The Oil in the Spring

Used oil contains acids that can slowly corrode metal components. Prior to storage, change the oil to remove acidic byproducts and ensure maximum protection throughout the summer. After changing oil, I like to run the engine for a couple minutes to distribute oil throughout the lower end of the engine.

Fog the engine

Use fogging oil to protect the upper end (cylinder, piston, valves) from corrosion during storage. Remove the spark plug, which provides the perfect time to inspect its condition, and spray a little oil into the cylinder. Slowly pull the starter cord a few times to distribute the oil, then replace the plug.

Check the gear housing – It can fail!

Clean any debris from around the filler port on the auger gear housing, remove the plug and ensure the gear lube level is up to the top. If not, add the correct lubricant (check your owner’s manual for viscosity).

Inspect belt condition and linkages

Stressing a worn belt after it’s sat idle for months is a recipe for a breakdown. When a belt does break, it’s often while clearing the first big snowfall of the year. Spring is the prime time to check the condition of drive belts and linkages. It’s much easier and far more comfortable to crawl around your snowblower on a mild, spring day than in the winter.

One final word of advice: Keep an eye on the weather at the start of winter. When the forecast calls for the first snowstorm of the season, start your snowblower a few days early to ensure it’s ready to go.

That gives you plenty of time if your snowblower won’t start – like about two hours on Thanksgiving day – to fix any problems.

How Engine Sludge Forms. And How To Prevent It.

AMSOIL Signature Series virtually prevented engine sludge on this oil pick-up screen.

Engine Sludge Is Easily Avoidable

Engine sludge.

It’s a back gelatinous substance that wreaks havoc in engines. And long before the engine’s demise, engine sludge can foul engine sensors and interfere with performance. Some mechanics call it the “black death.”

How does motor oil, which is fluid, become a semi-solid paste or gel inside an engine?

Here’s what we’ll cover:

  • How engine sludge forms
  • The effects of engine sludge
  • Synthetic oil helps prevent engine sludge
  • High-quality additives fight engine sludge
  • Severe service invites engine sludge

How engine sludge forms

Engine sludge is the result of a series of chemical reactions.

The lubricant degrades as it is exposed to oxygen and elevated temperatures. The higher the temperature, the more rapid the rate of degradation. In fact, every 18°F (10°C) increase in temperature doubles the rate of oxidation.
Many people still believe any oil is fine as long as you change it often but 95% of the brands out there do not address that inch of protection when you really need it!! We’ve all had issues where the engine is overheating or some situation where adequate lubrication isn’t available. AMSOIL offers 75% more protection when you need it and our diesel oils offer 6X more protection than required by industry testing.

The by-products of this reaction form highly reactive compounds that further degrade the lubricant. Their by-products react with other contaminants, forming organic acids and high-molecular-weight polymeric products. These products further react, forming the insoluble product known more commonly as sludge.

What begins as a thin film of lacquer or varnish deposits on hot or cold metal surfaces and bakes into an expensive mess.

The effects of engine sludge

Sludge can block the oil passages and oil-pump pick-up screen, resulting in oil starvation. Often, the negative effects are cumulative rather than sudden.

Many engines with variable valve timing (VVT) use oil-pressure-operated mechanical devices to change valve timing, duration and lift. Sludge can plug the solenoid screen or oil gallies and impact the operation of VVT mechanisms, eventually leading to a costly repair bill. Sludge reduces efficiency and increases time and money spent on maintenance.

Who doesn’t want a cooler engine? Sludge, even the early stages prevents the engine from dispersing heat efficiently. Why would you risk a Group III “synthetic” which does leave deposits adding to or resulting into an engine which struggles to exhaust heat.

Synthetic oil helps prevent engine sludge

Fortunately, sludge and varnish deposits are something oil manufacturers can control. Using thermally stable synthetic base oils reduces the rate of degradation (oxidation). (Yes – and that is “Real 100%” Synthetics – not the ones they currently call “Fully”..

Anti-oxidant additives help reduce the rate of degradation as well. One of the most widely used is zinc dithiophosphate. Not only is it an excellent oxidation inhibitor, it is an outstanding anti-wear additive as well.

High-quality additives fight engine sludge

We can further address many of the issues occurring after the initial oxidation stage.

Additives, such as detergents and dispersants, are commonly part of motor oil formulation. They help promote the suspension of contaminants within the oil and keep them from agglomerating.

Detergents, which are also alkaline in nature, assist in neutralizing acids generated in the sludge-building process. Anti-oxidant, dispersant and detergent additives are consumed during use.

To achieve maximum life expectancy, use an oil with high concentrations of anti-oxidant, dispersant and detergent additives.

AMSOIL Signature Series Synthetic Motor Oil, for example, has 50 percent more detergents* to help keep oil passages clean and promote oil circulation. It provides 90 percent better protection against sludge**.

Signature Series Synthetic Motor Oil was subjected to the Sequence VG test to measure its ability to prevent sludge. Signature Series produced an oil pick-up tube screen virtually free from sludge. Our unique combination of detergents and high-quality base oils control oxidation and sludge to keep engines clean and efficient.

PDF of the test where AMSOIL has this done (Southwest Research)

AMSOIL Signature Series virtually prevented engine sludge on this oil pick-up screen.

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Severe service invites engine sludge

Equipment operating conditions also influence the likelihood of sludge or varnish issues.

Stop-and-go driving, frequent/long-term idling and operation in excessively hot or cold weather can increase the likelihood of sludge and varnish, especially if using more volatile conventional oils. If sludge has already formed, you can use an engine flush to clean sludge from your engine.

Interestingly, most auto manufacturers note in their owner’s manual that operation under any of the above conditions is considered severe service and requires more frequent oil changes.

From a mechanical standpoint, things like adding too much oil to the oil sump, antifreeze contamination, excessive soot loading, excessive oil foaming, poor engine-combustion efficiency, excessive blow-by and emission-control-system issues can all lead to the formation of sludge and varnish.

By practicing good maintenance and using properly formulated, premium synthetic lubricants, like AMSOIL synthetic motor oil, your vehicle won’t succumb to the “black death.”

Taking it a step further which many of our customers do – to make sure your vehicle is always running in peak condition one thing is to have your oil analyzed. I do it not so much to see how the oil is doing but to measure what may be going on in the engine to deplete detergents or to test for any out of typical wear levels, fuel in the crankcase, and to see if the viscosity is still on par.  Oil analysis kits are easy to use especially when you have the dipstick extraction pump.

*vs. AMSOIL OE Motor Oil
**Based on independent testing of AMSOIL Signature Series 5W-30 in the ASTM D6593 engine test for oil screen plugging as required by the API SN PLUS specification.