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20W-50 Synthetic Premium Protection Motor Oil (ARO)
20W-50 Premium Protection Motor Oil (ARO)

For use in both diesel and gasoline engines. Ideal for applications where the extra protection of a higher-viscosity oil is desired. The higher viscosity may help reduce motor oil consumption in equipment experiencing higher than normal oil usage rates while running lower viscosity lubricants.

Package sizes include:

Quart Bottle
Gallon Bottle
16-Gallon Keg
30-Gallon Drum
55-Gallon Drum

Product Code: ARO • Brand: AMSOIL




MSDS Data Sheet

Product Details Tech Data Reviews & Rating

Product Applications
AMSOIL Synthetic 20W-50 Premium Protection Motor Oil is a multi-use, premium synthetic lubricant for applications that require or benefit from a higher viscosity oil. It is recommended for air and liquid cooled, large or small gasoline and diesel engines, transmissions and chaincase applications where 20W-50 oil is required with any of the following specifications:

Product Application Specs

• API SL, SJ, SH, SG
• API CI-4 Plus, CH-4, CF, CF-2
• ISO-L-EMA
• Caterpillar ECF-1
• JASO MA (Motorcycle)
• MAN 271/3275
• MTU Type 2
• Cummins 20071/20072/20076/20077
• VDS-2, VDS
• Mack EO-M+
• ACEA A3/B3, E3, E5
• MB 228.3, 229.1
• Detroit Diesel 93K214

Product Description
AMSOIL Premium Protection Synthetic Motor Oil is formulated to provide superior protection and performance in a wide variety of demanding applications. Its unique combination of synthetic base stocks and a superior additive package results in a formulation that exceeds the requirements of most gasoline or diesel applications that call for 20W-50 motor oil. Premium Protection Synthetic Motor Oil is ideal for high-mileage vehicles and high-stress vehicles subject to hot temperatures, heavy hauling, trailer pulling or off-road use. It provides the extra anti-wear protection required by engines with flat-tappet cams and high-tension valve springs. AMSOIL Premium Protection Synthetic Motor Oil offers flexibility and performance beyond conventional oils for convenience and trouble-free operation.

AMSOIL, the leader in automotive synthetic lubrication, produced the world’s first API qualified synthetic motor oil in 1972. Trust the extensive experience of AMSOIL The First in Synthetics® to do the best job protecting your engine.

Superior Wear Protection
AMSOIL Premium Protection Synthetic Motor Oil is high-viscosity oil engineered to protect against metal-to-metal contact. It resists viscosity shear and is formulated with a heavy treatment of zinc and other anti-wear additives for excellent protection of gears, bearings, cam lobes and other high-pressure components in engines and transmissions. AMSOIL Premium Protection Synthetic Motor Oil helps extend equipment life.

Wet Clutch Compatible
AMSOIL Premium Protection Synthetic Motor Oil contains no friction modifiers, making it ideal for motorcycles, maintenance equipment and other wet-clutch transmission applications. Formulated to prevent clutch glazing and slippage, it helps ensure smooth clutch engagement and long-term, dependable transmission operation. Premium Protection Synthetic Motor Oil reduces clutch wear for extended transmission life.

Resists Oxidation and High-Temperature Breakdown
AMSOIL Premium Protection Synthetic Motor Oil is specifically formulated to overcome the thermal deficiencies common to conventional petroleum oils. Volatilization (burn-off), oxidation and excessive deposit formation from high heat are greatly reduced. Viscosity thickening is controlled and engines run cleaner, promoting cooler operation and long engine life in air or liquid-cooled engines. In addition, the higher viscosity nature of AMSOIL 20W-50 Synthetic Motor Oil may help reduce motor oil consumption in equipment that experiences higher-than-normal usage rates when lower-viscosity lubricants are installed.

Extends Drain Intervals in Gasoline and Diesel Engines
Superior AMSOIL synthetic base stock and additive technology exceeds the requirements of both gasoline and diesel engines. AMSOIL Premium Protection Motor Oil is designed to neutralize acids, disperse soot and last longer in service than conventional oils.

MIXING AMSOIL
AMSOIL Synthetic 20W-50 Premium Protection Motor Oil is compatible with conventional and synthetic motor oils. Mixing AMSOIL motor oils with other oils, however, will shorten the oil life expectancy and reduce the performance benefits. AMSOIL does not support extended drain intervals where oils have been mixed. Aftermarket oil additives are not recommended for use with AMSOIL Synthetic Oils.

SERVICE LIFE
AMSOIL Synthetic 20W-50 Premium Protection Motor Oil is recommended for extended intervals in unmodified, mechanically-sound vehicles or equipment as follows:

Diesel Engine Service
•Normal Service - Up to 25,000 miles or one year, whichever comes first, or longer based on oil analysis.
•Severe Service - Up to 15,000 miles or one year, whichever comes first, or longer based on oil analysis.

Gasoline Engine Service
•Normal and Severe Service - Up to 15,000 miles or one year, whichever comes first, or longer based on oil analysis.

Motorcycles, Small Engines, Stationary Engines, Heavy Equipment and Other Applications
•Extend drain intervals based on oil analysis or follow the manufacturer-recommended drain interval.

AMSOIL Ea™ Full-Flow Oil Filters are designed for extended drain intervals. They stop smaller particles, flow more oil and last longer than regular filters. For best performance, use AMSOIL Ea™ Full-Flow Oil Filters and replace at the time of oil change. Other oil filters should be changed at standard OEM* intervals.

*OEM - Original Equipment Manufacturer

HEALTH & SAFETY
This product is not expected to cause health concerns when used for the intended application and according to the recommendations in the Material Safety Data Sheet (MSDS).

Click here to view the MSDS Data Sheet for AMSOIL ARO.

Keep out of the reach of children. Don't pollute. Return used oil to collection centers.

TYPICAL PHYSICAL PROPERTIES
AMSOIL High Performance Synthetic 20W-50 Motor Oil (ARO)
Kinematic Viscosity @ 100°C, cSt (ASTM D-445) 18.9
Kinematic Viscosity @ 40°C, cSt (ASTM D-445) 123.8
Viscosity Index (ASTM D-2270) 172
CCS Viscosity @ -15°C, cP (ASTM D-5293) 3525 (-15)
Pour Point °C (°F) (ASTM D 97) -36 (-33)
Flash Point °C (°F) (ASTM D 92) 233 (451)
Fire Point °C (°F) (ASTM D-92) 249 (480)
High Temperature/High Shear @ 150°C and 1.0 X 106 s-1, cP (ASTM D 4683), cP 5.0
Four Ball Wear Test (ASTM D 4172 @ 40 kgf, 150°C, 1800 rpm, 1 hour, Scar in mm) 0.40
Noack Volatility, % weight loss (g/100g) (DIN 51581) 6.5
Total Base Number 12.1

Did this product meet your expectations?

(click on a star to rate)
Product Name: 20W-50 Synthetic Premium Protection Motor Oil (ARO)
Current Rating: 4.94 out of 5 stars
Total Votes: 33 vote(s)

A Verified Buyer is an individual who has purchased the reviewed product and submitted their review through a specific process that tracks purchase history.Reviewed by Bradley: space

Have used this product for years

Porsche 911 air cooled

Item Reviewed: Premium Protection Motor Oils (AMO,ARO)

A Verified Buyer is an individual who has purchased the reviewed product and submitted their review through a specific process that tracks purchase history.Reviewed by James: space

Yes

Purchased for use in an inboard v 6 boat engine. Great oil for this application.

Item Reviewed: Premium Protection Motor Oils (AMO,ARO)

A Verified Buyer is an individual who has purchased the reviewed product and submitted their review through a specific process that tracks purchase history.Reviewed by Cecil: space

I would buy this again and again

Great product

Item Reviewed: Premium Protection Motor Oils (AMO,ARO)

A Verified Buyer is an individual who has purchased the reviewed product and submitted their review through a specific process that tracks purchase history.Reviewed by Richard: space

Love This Oil

Love this oil, the full synthetic oil I was using can not even hold a candle to AMSOIL. The engine runs so smooth and much more quietly : )

I also went from a 5w30 to the 10w40 for the summer, will change back to the 5w30 for the winter.

When I'm ready for a transmission fluid change I'm changing over to AMSOIL too.
Richard

Item Reviewed: Premium Protection Motor Oils (AMO,ARO)

A Verified Buyer is an individual who has purchased the reviewed product and submitted their review through a specific process that tracks purchase history.Reviewed by Joey: space

Amazing oil

Bought this oil for our 2015 Scag Cheetah, so far it's amazing, it seems to run way better, and for some reason it doesn't pop anymore when starting it. It has a 31 hr Kawasaki motor . Our dealer told us to use 20 w50 in it, now I gotta cross reference the oil filter and order some.

Item Reviewed: Premium Protection Motor Oils (AMO,ARO)

A Verified Buyer is an individual who has purchased the reviewed product and submitted their review through a specific process that tracks purchase history.Reviewed by Adam: space

Good stuff

Product does wonders in the evo. The turbo requires high zinc so this does the job.

Item Reviewed: Premium Protection Motor Oils (AMO,ARO)

A Verified Buyer is an individual who has purchased the reviewed product and submitted their review through a specific process that tracks purchase history.Reviewed by Shawn: space

I would purchase this product again.

This Amsoil Motor Oil is used in a track car that constantly see's high RPM pulls on a road race course. Works well and oil temps seem to stay steady throughout a 20-30 minute session. Am pleased with the product and will continue to use it. It's what I would call "cheap insurance".

Item Reviewed: Premium Protection Motor Oils (AMO,ARO)

A Verified Buyer is an individual who has purchased the reviewed product and submitted their review through a specific process that tracks purchase history.Reviewed by Thor: space

High zinc oil that is durable

The Amsoil high zinc formula is all i use in my bbc. This oil holds up to the heat and high compression of my street/strip motor.

Item Reviewed: Premium Protection Motor Oils (AMO,ARO)

A Verified Buyer is an individual who has purchased the reviewed product and submitted their review through a specific process that tracks purchase history.Reviewed by George: space

Will buy again

I will continue to purchase nothing but AMSOIL for all our lubrication needs. Classic cars, snowmobiles, 4 wheelers, and our daily drivers. Gas and diesel. And dont forget the boats. It's one place for everything, shipped to my door.

Item Reviewed: Premium Protection Motor Oils (AMO,ARO)

A Verified Buyer is an individual who has purchased the reviewed product and submitted their review through a specific process that tracks purchase history.Reviewed by Hilton: space

I would by this product again

Dad wanted an upgraded oil in his new F250 and I knew this company produces the best oil and I also run this in my Dixie chopper.

Item Reviewed: Premium Protection Motor Oils (AMO,ARO)

A Verified Buyer is an individual who has purchased the reviewed product and submitted their review through a specific process that tracks purchase history.Reviewed by Thomas: space

I have been using this for the last 300000 miles.

Great oil for my diesel pickup.

Item Reviewed: Premium Protection Motor Oils (AMO,ARO)

A Verified Buyer is an individual who has purchased the reviewed product and submitted their review through a specific process that tracks purchase history.Reviewed by Randall: space

The best dual use oil ever!

Great oil for street and track. Got my 996 oil analysis back after 6 months, multiple track days and of course...perfect results! Keep up the great work!

Item Reviewed: Premium Protection Motor Oils (AMO,ARO)

A Verified Buyer is an individual who has purchased the reviewed product and submitted their review through a specific process that tracks purchase history.Reviewed by D: space

Nothing but Amsoil!

The absolute best of the best. I use it in everything. Every engine I use this oil in has never given me any kind of oil related problems. If you want your engines to last this is the oil to use.

Item Reviewed: Premium Protection Motor Oils (AMO,ARO)

A Verified Buyer is an individual who has purchased the reviewed product and submitted their review through a specific process that tracks purchase history.Reviewed by Otis: space

No issues.

This oil is used in an extreme situation. Been a customer for years. No issues or failures

Item Reviewed: Premium Protection Motor Oils (AMO,ARO)

A Verified Buyer is an individual who has purchased the reviewed product and submitted their review through a specific process that tracks purchase history.Reviewed by Raycer: space

Works

I changed from the boosted version which lowered my my oil pressure way to much. Now my oil pressure never drops below 40 psi. With the boosted version it dropped to the 25 psi.

Item Reviewed: Premium Protection Motor Oils (AMO,ARO)

A Verified Buyer is an individual who has purchased the reviewed product and submitted their review through a specific process that tracks purchase history.Reviewed by Johnny Racer: space

Great Product

I've been using this oil for 10 years in my 1995 BMW 325 which is a track/race car only. I put about 2000 miles a year on it and change the oil once a year. The engine is very happy runs like a top and I have 125,000 miles on it.

Item Reviewed: Premium Protection Motor Oils (AMO,ARO)

A Verified Buyer is an individual who has purchased the reviewed product and submitted their review through a specific process that tracks purchase history.Reviewed by Keith: space

Best Synthetic Lubricants

I'm 65 years old and have been into automotive lubricants since I was a teenager. Out of all of the Automotive lubricants I have purchased and tested over the years. Nothing surpasses Amsoil products. Unlike most, I still change my engine oils at 3000 miles. That being said, I own a 1988 BMW M5 with almost 200K miles which still runs like it just rolled off the show room floor. There are many other brands and types of oils I consider to be excellent but nothing come close to Amsoil. It's the most trust high grade lubercants I have found to date and will NOT use any other brand.

Item Reviewed: Premium Protection Motor Oils (AMO,ARO)

A Verified Buyer is an individual who has purchased the reviewed product and submitted their review through a specific process that tracks purchase history.Reviewed by Robert: space

Love amsoil

I use this in my old hot rods and love it again was useing other synthetic oils but none of them are close to amszoil.

Item Reviewed: Premium Protection Motor Oils (AMO,ARO)

A Verified Buyer is an individual who has purchased the reviewed product and submitted their review through a specific process that tracks purchase history.Reviewed by Kubs: space

The only oil for my Street class Corvette Race Car

I put this in my 2002 base model Corvette, and:
-became the overall Top Eliminator at the NCCC convention 2017. (although I'm not a drag racer)
-Finished 2nd in Autocross.
-Set at track record at Putnam Park race way.
-Ran all day - two days in a row- at a track event at NCM.

with all the things to worry about when racing a street car, I can check Oil and Engine concerns off the list.

Item Reviewed: Premium Protection Motor Oils (AMO,ARO)

A Verified Buyer is an individual who has purchased the reviewed product and submitted their review through a specific process that tracks purchase history.Reviewed by Roy: space

Great oil for modified turbo motors

My modified Subaru makes over 100 hp per cylinder so I need a very stout oil. This stuff pours like water, but has a very high viscosity at high temps. It also has loads of zinc and phosphorus which makes it perfect for high horsepower applications, turbo engines, and american hot rods.

Item Reviewed: Premium Protection Motor Oils (AMO,ARO)

A Verified Buyer is an individual who has purchased the reviewed product and submitted their review through a specific process that tracks purchase history.Reviewed by Joe: space

Great product!

350,000 miles on 98 Chevy, started using in the 90,000, don't have to worriy about oil changes , being over due.

Item Reviewed: Premium Protection Motor Oils (AMO,ARO)

A Verified Buyer is an individual who has purchased the reviewed product and submitted their review through a specific process that tracks purchase history.Reviewed by LouFa: space

90-95 LT5 motor oil

Previously used Mobile 1 for years, but the specifications changed over time and didn't meet the GM specs for the engine. I transitioned to Amsoil and the engine ran even quieter and I know it's getting the proper lubrications that GM intended for the DOHC LT5.

Item Reviewed: Premium Protection Motor Oils (AMO,ARO)

A Verified Buyer is an individual who has purchased the reviewed product and submitted their review through a specific process that tracks purchase history.Reviewed by Voganni: space

Amazing product

Wonderful oil for older engines that can use it. I routinely run it for years at a time in my tractor and pickup. Neither uses any oil.

Item Reviewed: Premium Protection Motor Oils (AMO,ARO)

A Verified Buyer is an individual who has purchased the reviewed product and submitted their review through a specific process that tracks purchase history.Reviewed by Scott: space

Only Reliable Oil Left at Affordable Price

There are no other decent high-quality 20W50 oil products around for this price. Cannot think of a better value, at least on West Coast. Engine runs just as dependably, even out of a tire slide, as when brand new.

Item Reviewed: Premium Protection Motor Oils (AMO,ARO)

A Verified Buyer is an individual who has purchased the reviewed product and submitted their review through a specific process that tracks purchase history.Reviewed by Josh: space

Great product

Use this oil in an old 1975 Chevy small block racing application. Like the high zinc concentrate

Item Reviewed: Premium Protection Motor Oils (AMO,ARO)

A Verified Buyer is an individual who has purchased the reviewed product and submitted their review through a specific process that tracks purchase history.Reviewed by Ed: space

Been using for years.

The filler spout is too big to fit all of my bikes cars & trucks. Like the oil.

Item Reviewed: Premium Protection Motor Oils (AMO,ARO)

A Verified Buyer is an individual who has purchased the reviewed product and submitted their review through a specific process that tracks purchase history.Reviewed by Allen: space

Yes

Race application

Item Reviewed: Premium Protection Motor Oils (AMO,ARO)

A Verified Buyer is an individual who has purchased the reviewed product and submitted their review through a specific process that tracks purchase history.Reviewed by XS: space

100% Satisfaction all the time

I have never regretted the day I made the switch to AMSOIL products. I am currently using the 20W 50 Full Synthetic in my Race Engine 4AGE 20V Turbo Charged. Engine Runs way smoother, even the initial startup in the mornings is way quieter.

I have recently Purchased there radiator Coolant and I am eager to have this installed. I am Happy, and Highly recommend AMSOIL Products to anyone who wants to protect there machinery, equipment or motor. A++ AMSOIL For LIFE......

Item Reviewed: 20W-50 Synthetic Premium Protection Motor Oil (ARO)

A Verified Buyer is an individual who has purchased the reviewed product and submitted their review through a specific process that tracks purchase history.Reviewed by Scott: space

works great

Use this in my John Deere Diesel engines as well as my Chevy Trucks

Item Reviewed: Premium Protection Motor Oils (AMO,ARO)

A Verified Buyer is an individual who has purchased the reviewed product and submitted their review through a specific process that tracks purchase history.Reviewed by Dom The Bomb: space

I will buy this oil continuously. It keeps my rotary running

The heacier weight oils are to die for if you own a rotary engine in a warmer climate. Amsoil delivers when it comes to their 20w50 synthetic oil.

Item Reviewed: 20W-50 Synthetic Premium Protection Motor Oil (ARO)

A Verified Buyer is an individual who has purchased the reviewed product and submitted their review through a specific process that tracks purchase history.Reviewed by Steve: space

Yes I will buy this product again.

I am using this oil in my 68 Charger. And I am very happy with the results.

Item Reviewed: 20W-50 Synthetic Premium Protection Motor Oil (ARO)

A Verified Buyer is an individual who has purchased the reviewed product and submitted their review through a specific process that tracks purchase history.Reviewed by gene: space

yes

good oil

Item Reviewed: 20W-50 Synthetic Premium Protection Motor Oil (ARO)

A Verified Buyer is an individual who has purchased the reviewed product and submitted their review through a specific process that tracks purchase history.Reviewed by Steve S.: space

Only the best for this 94 Rover!

Made the switch from conventional oil to Amsoil and appreciate the quicker startup, better throttle response & quieter engine operation on my 94' Discovery. 340K km on the clock & looking forward many more with Amsoil. Thanks for a great product & service!

Item Reviewed: 20W-50 Synthetic Premium Protection Motor Oil (ARO)

A Verified Buyer is an individual who has purchased the reviewed product and submitted their review through a specific process that tracks purchase history.Reviewed by mac: space

Premium Protection 20W-50 Synthetic Motor Oil

I am using this oil in my 95 GMC Sierra SLE. with a V8 5 litre. The oil makes the engine run smoother and quieter. Gas mileage seems better. The gas needle doesn't drop as quickly. I have been using it for 2 months. so far no leaks, no oil consumption. Acceleration is good.

Item Reviewed: 20W-50 Synthetic Premium Protection Motor Oil (ARO)

A Verified Buyer is an individual who has purchased the reviewed product and submitted their review through a specific process that tracks purchase history.Reviewed by Small engine Dr.: space

I will reorder this oil again.

Oil lasts longer in my older vehicle and I don't have to add any between oil changes.

Item Reviewed: 20W-50 Synthetic Premium Protection Motor Oil (ARO)

A Verified Buyer is an individual who has purchased the reviewed product and submitted their review through a specific process that tracks purchase history.Reviewed by racer270: space

Premium Protection 20W-50 Synthetic Motor Oil , high zinc

i love the product , i drive less then 12,000 miles
and so i have been changing my oil once a year ,

since 2007 when i overhauled my dodge diesel engine.
in fact it's cheaper then running Dino oil ,.. and changing it every 3,000 ~ 4,000 miles.

thank you for the grate product.

GA.

Item Reviewed: 20W-50 Synthetic Premium Protection Motor Oil (ARO)

A Verified Buyer is an individual who has purchased the reviewed product and submitted their review through a specific process that tracks purchase history.Reviewed by HD: space

Been using it for years

Works great lasts a long time. Use it in my small engines. Lawn mowers , pressure washers, etc.

Item Reviewed: 20W-50 Synthetic Premium Protection Motor Oil (ARO)

A Verified Buyer is an individual who has purchased the reviewed product and submitted their review through a specific process that tracks purchase history.Reviewed by None: space

Yes

Excellent product.

Item Reviewed: 20W-50 Synthetic Premium Protection Motor Oil (ARO)

A Verified Buyer is an individual who has purchased the reviewed product and submitted their review through a specific process that tracks purchase history.Reviewed by Brent: space

This product has helped keep my hydro pump working great

I have a z turn mower with over 3000 hrs on one of the pump I have used this product to extend the life way past normal factory suggested hrs

Item Reviewed: 20W-50 Synthetic Premium Protection Motor Oil (ARO)

A Verified Buyer is an individual who has purchased the reviewed product and submitted their review through a specific process that tracks purchase history.Reviewed by Bob: space

I've used amsoil for over ten years and had no problems

It's a great product, I even get,an extra 2 miles per gallon which helps a lot

Item Reviewed: 20W-50 Synthetic Premium Protection Motor Oil (ARO)

A Verified Buyer is an individual who has purchased the reviewed product and submitted their review through a specific process that tracks purchase history.Reviewed by Mike: space

Wouldn't stop buying

Best oil out there, checked dip stick after 2000 miles looks like I just changed the oil

Item Reviewed: 20W-50 Synthetic Premium Protection Motor Oil (ARO)

A Verified Buyer is an individual who has purchased the reviewed product and submitted their review through a specific process that tracks purchase history.Reviewed by PAUL: space

Great oil for older big block engines

Use this oil in my big block mercury marine 454 inboard engines. Makes them run smooth and quiet. there is never any problem starting these engines, even after being stored for the long Canadian winter. The oil also help performance with at least a 20 hp power increase!

Item Reviewed: 20W-50 Synthetic Premium Protection Motor Oil (ARO)

A Verified Buyer is an individual who has purchased the reviewed product and submitted their review through a specific process that tracks purchase history.Reviewed by David: space

Great oil

Since I started using this oil in 2006 I'm satisfied with its performance. I use it in a 3406E caterpillar engine. The engine runs cooler and more fuel efficient. Very happy with the ARO 20W/50.

Item Reviewed: 20W-50 Synthetic Premium Protection Motor Oil (ARO)

A Verified Buyer is an individual who has purchased the reviewed product and submitted their review through a specific process that tracks purchase history.Reviewed by Rob: space

I've been using amsoil for years

Great product , I have 3 high mileage cars that I change every 8-10k miles and they are running strong.

Item Reviewed: 20W-50 Synthetic Premium Protection Motor Oil (ARO)
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