The Best Conventional Motor Oils
Shopping for engine oil can be daunting, with numerous brands and options available in today’s marketplace. How do you choose from all the different companies offering motor oil when they all sound the same? Well, truth be told, most reputable brands will offer similar products, and in the case of this list, you really can’t go wrong with any of the options. Some oils are better quality than others, offering more performance and working harder to keep your engine clean. But many would argue that the general consumer won’t even notice the difference between Quaker State or Pennzoil. In fact, there have been studies conducted that show most oil brands have similar products.
In this article, we’ll take a look at the best motor coils available—but only conventional motor oils. If you’re searching for the best synthetic motor oils, click here. Conventional motor oil is generally the most affordable engine oil you can purchase and offers basic protection for most engines. Generally, the majority of automakers will use conventional motor oil in a vehicle when it rolls off the assembly line for the break-in period, after which some owners will upgrade to semi-synthetic or fully synthetic oil. But for most ordinary drivers, conventional motor oil is sufficient in maintaining your engine’s performance and life.
Where the performance of conventional motor oils suffer compared to synthetic oils is in extreme temperatures, and you’ll need to do more frequent oil changes. Ever heard that your car’s oil should be changed every 3,000 miles? That’s likely because it uses conventional motor oil.
We’ll detail more information you need to know about conventional motor oil after our product suggestions. For more information on the top 10 best motor oils, refer to our table of contents.
Table of contents
- 1. Editor's Pick: Castrol GTX Motor Oil
- 2. Valvoline Daily Protection Motor Oil
- 3. Quaker State Advanced Durability Motor Oil
- 4. AmazonBasics Motor Oil
- 5. Havoline Motor Oil
- 6. Pennzoil Motor Oil
- 7. Lucas Oil Hot Rod & Classic Motor Oil
- 8. Formula Shell Motor Oil
- 9. STP Motor Oil
- 10. ACDelco Professional Motor Oil
- Why is Motor Oil Important?
- What Are All These Numbers and Letters?
- How to Change Your Car's Engine Oil: a Breakdown by Kshitij Sharma
- Tools Required
- The Procedure
- Recent Updates
1. Editor's Pick: Castrol GTX Motor Oil
A premium conventional motor oil that has been around since the late 1960s, Castrol GTX is our top pick due to its reputation, price, and overall popularity even on Amazon. This motor oil is designed to offer superior protection against engine sludge (as measured in the Sequence VG Sludge Test), along with advanced protection against viscosity and thermal breakdown. It's formulated with premium quality base oils and anti-wear additives that help extend the life of your engine.
Castrol GTX is available as a 6 pack of 1-quart bottles, a 5-quart jug, 3 pack of 5-quart jugs, and a 6-gallon bottle. Choose from 10W-30 or 10W-40 viscosities. You can also choose from High Mileage, Synthetic, and High Mileage Synthetic options as part of Castrol's GTX lineup.
Product features:
- Extremely popular and reputable brand
- Superior protection against sludge—as measured in the Sequence VG Sludge Test
- Advanced protection against viscosity and thermal breakdown
- Formulated with premium quality base oils and anti-wear additives
- Helps extend the life of your engine
- Available in (6) 1-quart bottles, 5-quart jug, (3) 5-quart jugs, 6-gallon bottle
- 10W-30 and 10W-40 viscosities
2. Valvoline Daily Protection Motor Oil
Formulated with advanced additives for year-round engine protection is Valvoline's Premium Conventional Motor Oil. The company's lineup of motor oils is available in multiple viscosities: 10W-30, 10W-40, 20W-50, SAE 30, SAE 40, and SAE 50. Amazon offers Valvoline's conventional motor oil in single units of 1- or 5-quart bottles, a 6 pack of 1-quart bottles, or a 3 pack of 5-quart bottles.
Valvoline uses added detergents to help protect against sludge and deposits, while high quality additives resist motor oil breakdown in tough conditions. The company's conventional motor oil meets the API SN Plus classification, protecting engines from Low Speed Pre-Ignition (LSPI).
In addition, each bottle features trademarked Easy Pull Tab, Precision Pour Spout, and Anti-Glug Tube.
Product features:
- Available in multiple viscosities: 10W-30, 10W-40, 20W-50, SAE 30, SAE 40, and SAE 50
- Select from single units of 1- or 5-quart bottles, (6) pack of 1-quart bottles, or (3) pack of 5-quart bottles
- Added detergents to protect against sludge and deposits
- High quality additives resist motor oil breakdown
- Meets API SN Plus classification
- Trademark features: Easy Pull Tab, Precision Pour Spout, and Anti-Glug Tube
3. Quaker State Advanced Durability Motor Oil
Quaker State's conventional motor oil is part of its Advanced Durability lineup and is available in a single 5-quart bottle, a 6 pack of 1-quart bottles, or a 3 pack of 5-quart bottles. Designed to protect against corrosion, Quaker State's Advanced Durability conventional motor oil contains acid-neutralizing additives to stop combustion acids from damaging your engine. Formulated to meet the fuel economy requirements of the GF-5 Industry standard, this oil meets or exceeds North American warranty requirements for worldwide automakers.
This oil will maintain viscosity grade from start to finish, giving your engine optimal protection so it can survive daily commutes, from sustained high-speed highway operation to repetitive stop-and-go traffic.
Product features:
- Available in (1) 5-quart bottle, (6) 1-quart bottles, or (3) 5-quart bottles
- Designed to protect against corrosion
- Acid-neutralizing additives stop combustion acids from damaging the engine
- Maintains viscosity grade from start to finish
- Meets fuel economy requirements of the GF-5 Industry standard
- Meets or exceeds North American warranty requirements for worldwide automakers
4. AmazonBasics Motor Oil
AmazonBasics may not be a well-known brand when it comes to the automotive industry, but in recent years, Amazon's own line of products has expanded at a rapid pace to all types of markets. This conventional motor oil is available in 0W-20, 0W-40, 5W-20, 5W-30, 5W-40, 10W-30, 10W-40, and 20W-50 viscosities. It can be purchased in a 1-gallon jug, a 5-quart bottle, or a 6 pack of 1-quart bottles.
Formulated to keep engines properly lubricated and protected, this affordable option is API SN and ILSAC GF-5 approved. It's designed to help prevent buildup that can cause rust and corrosion, AmazonBasics' conventional motor oil reduces friction for less engine wear. The oil has high resistance to viscosity and thermal breakdown, while also helping reduce exhaust emissions.
AmazonBasics' conventional motor oil is manufactured by Warren Distribution, Inc., which is North America's largest manufacturer of private label lubricants.
Product features:
- Affordable, like all AmazonBasics products
- Available in 0W-20, 0W-40, 5W-20, 5W-30, 5W-40, 10W-30, 10W-40, and 20W-50 viscosities
- Select from 1-gallon, 5-quart, or (6) 1-quart bottles
- API SN and ILSAC GF-5 approved
- Keeps engines properly lubricated and protected
- Prevents buildup that can cause rust and corrosion
- Reduces friction for less engine wear
- High resistance to viscosity and thermal breakdown
- Helps reduce exhaust emissions
- Manufactured by Warren Distribution, Inc.
5. Havoline Motor Oil
Havoline's conventional motor oil features Deposit Shield Technology, which the company says protects against deposit and sludge formation, while providing excellent protection of critical engine parts. This oil works to shield against thermal breakdown, while cleaning the engine and positive crankcase ventilation systems to minimize deposit formations under heavy load and stop-and-go traffic. Like other oils on our list, Havoline's conventional offering meets or exceeds warranty requirements of automakers that rely on an API SN motor oil.
All grades of Havoline's conventional motor oils are formulated with high quality base stocks and contain detergent, dispersant, wear control, antioxidant, corrosion inhibitor, and foam suppressant additives. A high level of dispersancy protects against deposit and sludge formation from constant traffic and sustained high temperature operation.
This oil is available in a 5-quart jug and can also be purchased in a pack of 3. Our link below takes you to the 5W-30 variant.
Product features:
- Available in a 5-quart jug or (3) 5-quart jugs
- Deposit Shield Technology protects against deposit and sludge formation
- Works to protect against thermal breakdown
- Cleans the engine and positive crankcase ventilation systems
- Meets or exceeds warranty requirements that rely on an API SN motor oil
- Formulated with high quality base stocks
- Contains detergent, dispersant, wear control, antioxidant, corrosion inhibitor, and foam suppressant additives
- High level of dispersancy protects against deposit and sludge formation
6. Pennzoil Motor Oil
From Pennzoil is its conventional motor oil that promises to clean up to 40% of engine sludge in the first oil change. It'll of course continue to clean on the second and subsequent changes, by gently lifting sludge deposits off engine surfaces and dissolving them safely into the oil. In addition, Pennzoil's formula controls high temperature oxidation and deposits, while offering enhanced emission system protection compared to GF-4 and earlier service categories.
Formulated with Active Cleansing Agents, this oil will continuously work to prevent dirt and contaminants from turning into performance-robbing deposits. It meets or exceeds requirements of ILSAC GF-5, API SN Plus, API SN and all previous categories, as well as Chrysler MS-6395.
All of Pennzoil's products are backed by the Pennzoil Lubrication Limited Warranty, offering coverage up to 300,000 miles or 10 years (whichever is first) if you exclusively use Pennzoil Platinum, Pennzoil Gold, Pennzoil High Mileage, or Pennzoil motor oil. The warranty covers 15 critical engine parts and is customized for each driver's specific OEM recommended oil change schedule.
Product features:
- Cleans up to 40% of engine sludge in first oil change
- Gently lifts sludge deposits off engine surfaces and dissolves them safely into the oil
- Controls high temperature oxidation and deposits
- Enhanced emission system protection
- Formulated with Active Cleansing Agents
- Meets or exceeds requirements of ILSAC GF-5, API SN Plus, API SN and all previous categories, as well as Chrysler MS-6395
- Backed by Pennzoil Lubrication Limited Warranty
7. Lucas Oil Hot Rod & Classic Motor Oil
Lucas Oil has a wide lineup of offerings, but one of its most popular conventional motor oils is this Hot Rod & Classic Motor Oil. Of course if you're not running a hot rod or classic, look at other oils Lucas Oil has to offer. Available in a 5-quart jug, this oil contains high levels of ZDDP (Zinc) that is necessary to protect flat tappet cams, lifters, and pushrods. Designed to provide excellent thermal stability in case of overheating, this oil contains special Lucas additives that protect against rust, corrosion, and dry starts that occur when a vehicle sits unused for a long period of time.
This oil is available in 10W-30, 10W-40, and 20W-50 and our link below will take you to the 10W-30 variant, but search if you'd like a different viscosity.
Product features:
- Specially formulated for hot rod and classic cars
- Available in 10W-30, 10W-40, and 20W-50 in 5-quart jug
- Contains high levels of ZDDP (Zinc) to protect flat tappet cams, lifters, and pushrods
- Provides excellent thermal stability
- Lucas additives protect against rust, corrosion, and dry starts
8. Formula Shell Motor Oil
Formula Shell's conventional motor oil is designed to offer protection against harmful deposits and acids, helping keep your engine run clean for a long time. This oil is formulated to improve fuel economy and works to provide protection against extremely high temperatures. If your car is equipped with a turbocharged engine, Formula Shell's oil also helps protect against low-speed pre-ignition. It's safe to use at anytime in an engine's life cycle and is fully compatible with conventional engine oils.
Formula Shell's conventional motor oil is available in 5W-20, 10W-30, 10W-40, and 20W-50 options, in either a 5-quart jug or a dozen 1-quart bottles.
Product features:
- Available in 5W-20, 10W-30, 10W-40, and 20W-50 viscosities
- Select from (12) 1-quart bottles or a 5-quart jug
- Offers protection for extremely high temperatures
- Formulated to improve fuel economy
- Fights harmful deposits and acids
- Protects against low-speed pre-ignition on modern turbocharged engines
- Can be used anytime in an engine's life cycle
9. STP Motor Oil
STP may not be as popular of a brand as Pennzoil or Quaker State, but it still offers an affordable, quality oil. Scientifically formulated to insulate your engine from wear and tear, this conventional motor oil controls sludge formation while cleaning vital engine components. Offering protection against rust and corrosion, STP says its oil helps reduce engine wear while maintaining fuel economy. The bottle also features a wider spout that makes it easier to pour.
Amazon offers half a dozen of 1-quart bottles in 5W-30 at an affordable price, which is the link below. If you need a different viscosity or lower quantity, be sure to search on the site.
Product features:
- Affordable 6 pack of 1-quart bottles
- Formulated to insulate your engine from wear and tear
- Controls sludge formation
- Cleans key engine components
- Protects against rust and corrosion
- Helps maintain fuel economy
- Wider spout makes it easier to pour
10. ACDelco Professional Motor Oil
ACDelco is General Motors' Original Equipment parts brand and is responsible for producing over 90,000 GM OE and other parts. This conventional motor oil meets U.S. standards for API SN service classification, along with meeting and exceeding ILSAC GF-5 energy conserving performance standards. Not surprisingly, it also meets manufacturers' warranty requirements for passenger car and light-duty trucks. Formulated with a premium mineral-based solution, this oil protects against high temperature deposits, as well as the formation of sludge and varnish deposits to keep your engine running clean. It also provides engine cleanliness by controlling thermal breakdown under normal driving conditions.
Product features:
- GM's OE parts brand
- Meets U.S. standards for API SN, meets and exceeds ILSAC GF-5, meets manufacturers' warranty requirements
- Formulated with a premium mineral-based solution
- Protects against high temperature deposits, formation of sludge and varnish deposits
- Controls thermal breakdown
Why is Motor Oil Important?
Unless you own an electric vehicle, your car's engine needs oil. Its main and most important function is to prevent friction inside your engine, since it's full of moving parts. Motor oil is essential to keep these parts lubricated so they work as efficiently as they were designed to function. And where there's friction, there's heat—which is also bad for an engine. Ever heard of overheating or even frying an engine? That's because the oil—of lack of it—wasn't doing its job.
In addition to preventing friction and heat buildup within your engine, quality motor oil will keep your engine clean by preventing rust, corrosion, and oxidation.
What Are All These Numbers and Letters?
When you're shopping for motor oil, you'll notice they're offered in different viscosities, which by definition is "a quantity expressing the magnitude of internal friction, as measured by the force per unit area resisting a flow in which parallel layers unit distance apart have unit speed relative to one another." That probably just made it more confusing.
Simply put, motor oils have an SAE (Society of Automotive Engineers) rating that explains the viscosity of the engine oil—how thin or thick it is. So let's breakdown what the SAE rating actually means.
Let's start by looking at a popular oil choice, 10W-30. The first set of numbers and letters (10W), means that particular oil has a viscosity grade of 10 when tested at colder temperatures. The "W" standards for winter. The following number after the dash is the viscosity grade of the oil when an engine's temperature is at 212ºF. If you live in an area that doesn't have extremely cold temperatures, you may not care about your oil's performance in the cold. And that's where oils that just say SAE 30 or SAE 50 come into play. Those oils have not been tested in cold temperatures.
If you do live in an area that experiences cold temperatures, you'll want an engine oil with low W viscosity. Low viscosity oil is recommended for cold starts, since the oil is thinner and can flow quicker through your engine.
How to Change Your Car's Engine Oil: a Breakdown by Kshitij Sharma
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Alright, so social distancing in is full swing and you are doing your part to help the world recover from this crisis. Just before this all went down though, you were scheduled in for an oil change. And that is driving you a little crazy, because you love your car. Every drive you take, no matter how short, you're worried about damaging the engine since you couldn’t change the engine oil.
But don’t worry, we have you covered. Changing your car's engine oil is far from a daunting task. It is quite simple and doesn’t take too long either. You do need to be careful and follow a procedure though—mostly to avoid making a mess.
Before you begin, however, you will need to check which engine oil the manufacturer recommends. The information is usually given in the owner’s manual. If you already have the recommended engine oil, let’s begin.
Tools Required
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Changing the engine oil is one of simplest processes when it comes to working on cars. If you want to start working on cars, changing the oil yourself is a good place to start.
You will need an oil pan, a socket wrench, latex gloves and a filter wrench. Though in some cases you can remove the filter by hand or by other hacks, we highly recommend you invest in the right tool. As for the socket wrench, the ⅜-inch is the most common size for the drain plug, though sizes can run between ¼-inch and ¾-inch.
Also, make sure you have the right oil filter for your car. The spin-on type is the most common oil filter. Plus, the location of the oil filter is given in the owner’s manual.
The Procedure
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There are two ways to go about changing the engine oil: the warm method and the cool method. The warm method is the more recommended one. You drive your car around the block a couple of times until the engine reaches the optimal temperature. Then park it on a level surface and let it cool for 10 to 15 minutes. This method thins the oil down so the flow is more uniform and the oil also gathers up all the minute impurities and debris them might be in the engine at the time.
SEE ALSO: How to Wax Your Car: A BreakdownThe cool method is the one we recommend and is especially useful for old cars. It also beneficial as the car is not driven there is no leftover pressure between the filter and the sump so the flow is more controllable. And if it’s an old car, it is a great way to check for coolant leaks as well.
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First, start off by parking your car on level ground. The sump is always tilted towards the drain plug to aid oil removal so you don’t need to place the car on a jack.
Next, place the oil pan underneath the drain plug. Make sure it is slightly off-center.
Undo the drain plug. If you are doing the cool method, get a small glass jar and let the initial oil drain into the jar. That way you can test if the coolant is leaking into the engine. The anti-freeze and water are typically heavier than oil and will settle at the drain plug and will drain out first.
Next, let the oil drain and get yourself a cup of coffee.
By the time you’re done with your coffee, the oil should’ve drained completely. The next step is to remove the oil filter.
Make sure you have ample grip and the wrench is snug before you turn it anti-clockwise to loosen the air filter. The oil will splash out so be prepared. And if you used the warm-up method, then the splash could be a bit more aggressive compared to the cold method.
Next, oil the seal of the new filter liberally with the new oil before screwing it back in. After the oil filter is in give it just a ¾ twist to tighten it. Do not over-tighten so you can easily remove it during the next oil change. Screw the drain plug back as well and follow the same procedure as the oil filter.
Now the final step, adding the oil into the engine. Pour about half in to the engine and then switch the car on for about five minutes. This helps the oil spread around and avoid overflow. Next pour in the rest, close the oil filler cap and you're done.
Finally, it is advisable that you drive the car for about 10 minutes before letting it rest for the rest of the day. Have fun.
Recent Updates
December 22, 2021: Updated outdated product links.
October 13, 2021: Added additional product links.
August 4, 2021: Removed promoted product recommendation.
January 21, 2021: Updated with a promoted product recommendation.
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Jason Siu began his career in automotive journalism in 2003 with Modified Magazine, a property previously held by VerticalScope. As the West Coast Editor, he played a pivotal role while also extending his expertise to Modified Luxury & Exotics and Modified Mustangs. Beyond his editorial work, Jason authored two notable Cartech books. His tenure at AutoGuide.com saw him immersed in the daily news cycle, yet his passion for hands-on evaluation led him to focus on testing and product reviews, offering well-rounded recommendations to AutoGuide readers. Currently, as the Content Director for VerticalScope, Jason spearheads the content strategy for an array of online publications, a role that has him at the helm of ensuring quality and consistency across the board.
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Guy who drove 1964 Volvo p1800 using Castrol oils went 4 millions miles.will any heavy duty oil will works???????????.
This section discusses conventional motor oil. When an engine has used conventional all its life it doesnt do well switching to synthetic as I can attest to.