Product Reviewed: SAE 5W-20 Signature Series 100% Synthetic Motor Oil (ALM)
Current Rating: 4.95 out of 5 stars
Votes & Reviews: 529 vote(s) and 1218 user reviews.
Reviewed by Steven: 
The only oil I trust in my RAM I have used this oil since my truck was new
Reviewed by Ray:
I use ss 5w-20 in my pickup, good startup when cold.
Reviewed by Ron:
I run a lot of highway miles. The truck has run smoother and is very quiet. I also notice that dry startup is much quieter. My mileage has stayed nearly the same.
Reviewed by Roy D.:
Have been using Amsoil in our cars and motorcycles now for over 20 years. Top notch product at a reasonable price.
Reviewed by Lucky247:
I have used AMS oil since the first oil change on my 2011 Kia Rio5 and now at 78,000 miles I believe I made the right choice. Car has never used oil even at 9000 mile oil changes. I highly recommend this product.
Reviewed by Clint:
There is really one side effect to using the signature series oil and that is everytime I get into my car now I can't tell if it is running or not now that I changed the oil. Sometimes I get into the car while it is running and push my push button to start it and inadvertently shut it off.
Reviewed by Butch:
I do not use any other product for autos
Reviewed by JOHN T.:
BEST OIL SOLD IN THE USA, NO MATTER WHAT TYPE OF CAR YOU DRIVE
Reviewed by Madmax:
Great product! I use the same oil in both my vehicles.
Reviewed by Hvymech:
Having used amsoil for many years I am sold on the product.however a recent occurrence
deserves mention. A 2004 Toyota Tundra belonging to my girlfriend has for the last 12 years
Had a mild knock at every cold startup that subsides as the engine warms up. I persuaded
Her to let me put Amsoil in on the last service. The knock was there at initial startup but I noted
Did not take near as long to quite. It has not made the sound since. 3000 + miles.
Reviewed by SeeDub:
OK, fewer oil changes, better gas milage, longer lasting engine, easier winter start ups, less foreign oil. Need I say more?
Reviewed by
NGCpt:
In the eighties my father started using Amsoil in our family vehicles. He explained the benefits of using Amsoil. Over the years I tried other brands. I came back to Amsoil! Living in Phoenix with extreme heat, I need the best oil for my vehicles. I only run Amsoil in our three vehicles, and my air cooled Harley. Amsoil stands up to what Mother Nature throws at us. Thanks for a great product!
Reviewed by Irv:
Very good oil
Reviewed by Scott:
You can trust that it's 100 % Synthetic and it also increased my mpg about 5% in my 2012 f250 6.7 Diesel Been using it ever since 3000 miles and now I have 68,000 miles very happy with the product
Reviewed by Paul:
I use no other oil in my truck. The simple fact that this oil not only performs to a high standard in the heat, it also out performs other oils in Canadian winters. Therefore, I use nothing else in my truck and I also use Amsoil in my 2015 Indian Chieftain.
Reviewed by Iceman139:
I drive my vehicle hard and fast and as in all my previous vehicles, I only use the highest quality and performing synthetic signature series oil as I feel it works well to protect my engine and I have never had a failure or worn out or blown up motor as my vehicles skirt around redline more often than not. Great protection and affordability and I can leave it in a little longer too knowing that the protection is there ( however I still change oil at 4500-5000 miles even though manufacturer says 8000)
Reviewed by KLB:
We as a family have 6 vehicle & all kinds of 4 & 2 cycle small engine equipment and we use Amsoil in everything!!!
Reviewed by Klb:
We as a family have 6 vehicle & all kinds of 4 & 2 cycle small engine equipment and we use Amsoil in everything!!!
Reviewed by Fred:
I always use Amsoil in my cars I race....never had a problem , been using it now for 8 years, five different cars !
Reviewed by koz:
I put 200 miles a day on my truck. conventional oils require me to take down time to change to often.
with this product I swap out the oil with way less frequency. saving time and money. And my engins run great till 200-250,000 miles. it is a great product .
Reviewed by Adam:
I love this oil. I've been running in a 2006 F-150 for 6 years now (which has known sliding issues) without a hitch. I take a sample once a year and send it to a lab to get tested to make sure the engine is healthy. I put 10,000 on the oil and only added one quart in the middle over an 18 month time span. The test came back great. There were some higher metal contents due to rough towing in the mountains, but that was to be expected after what I put it through. They recommended switching to 7-8k intervals or one year, if I kept up the abuse. As long as you are not doing heavy towing, this will definitely last you the year it is guaranteed, and then some.
Reviewed by Mr. Shine:
Amsoil has proven itself to our family over many years, and many different applications. Motorcycle, automobiles new and old, pickup truck, garden tractor, garden tools. We apply it to everything we can. The 5W20 has gone into our two Hyundai's both bought new. 2013 Sonata, and 2014 Elantra. Amsoil always surpasses expectations. Stays remarkably clean and right up to the full line on the dip stick.
Reviewed by Jeremey:
I have been using Amsoil for years. Started out using it in dirt bikes and ATV and now in all of my vehicles. Amsoil is nothing but quality and is a must if you care for your vehicles.
Reviewed by 2cyle:
Use this oil in my pickup an it keeps everything clean in eng have pushed more than 1 Nissan eng over 100k on this oil
Reviewed by Michael:
Using 5w20 Signature Series in new Ram 1500. Love the quality of Amsoil products. I can go long chang intervals without worrying about the oil breaking down.
Reviewed by dan:
great motor oil as is the entire amsoil line of products
Reviewed by Gunner:
This is supposed to be the best synthetic on the market. Everyone I talk to who are mechanics swear by it.
Reviewed by Desrah:
The Amsoil SS engine oil (5W-20) is a great product to help my aging vehicle drives performed like it was new. I can sense how fluid and effective my car responded to my daily high performances driving habits.
Reviewed by Trailhawker:
I use Amsoil for everything I can.
Reviewed by Herbie:
I use it in my 2500 chevy
Reviewed by Jams:
I have used this oil product since 2005 and love this synthetic old for the long life between oil changes.
Reviewed by BustedKnuckles:
Always wanted try Amsoil before, found an online dealer and decided to give it a shot. Great product to use. Use it for my daily driver and motorcycle.
I really like how the oil quarts do not have that annoying film you have to break after you remove the lid and the design of the oil container as well. You don't have to hold a particular way to avoid air rushing back in causing it to "glug" when pouring in the crank case.
I run Amsoil oil filters as well, they come plastic wrapped inside the box to avoid any contaminates from getting in the filter. Seeing the plastic wrapped oil filter was a first for me. Every other brand I've ever bought was unprotected in a cardboard box.
Thank you.
Reviewed by Greg:
Have used Amsoil Signature in all of our vehicles/equipment and have never encountered engine wear issues
Reviewed by Mike P:
I use AMSOIL in all my equipment. Cars motorcycle, diesel work truck, power washer and generator. There is absolutely no way to go wrong using the best there is. So that's why I do it
Reviewed by Bill G:
Used in a 2016 chevy spark.
Reviewed by Larry:
Once a year oil changes since car was new.
Reviewed by Isaiah:
Went to the 6mo. oil change ( 2) time and the oil after 6 months still looks clean.
Reviewed by Mr. HoneyDo:
I don't have any technical information, but I'm happy with the performance and mileage I'm getting in my Silverdado with a combined highway and stop and go daily commute.
Reviewed by Blake:
Total reliability. Better fuel economy, cleaner engine, longer mechanical life. One higher priced change per year, but only one per year. Best product guarantee in the industry!
Reviewed by Mikethedriver:
Have several very hi mileage vehicles.. jeep with 300k Two F series trucks 300k & 400 k. So when we purchased new truck we put the signature series 5-20 and an Ea. filter on it. We feel pretty good about it.
Reviewed by Vu Nguyen:
Great Product
Reviewed by Brbstafford:
Amsoil provides superior protection and lubercation and increases change intervals to a management level. Everything runs better!
Reviewed by Bill F.:
Due to the extreme heat in my area I, by choice opt to use the Signature Series 5W-20 Synthetic Motor Oil to protect the 6.2 motor in my 2011 Ford F 150 Limited.
Reviewed by Scout:
As usual the shipping was fast, the product received was the product purchased. The oil filter was a perfect fit.
Reviewed by therr850:
I have used exclusively synthetic oil since it became available many years ago. I believe AmsOil is the best synthetic available at this time. Less oil consumption and smoother engine operation.
Reviewed by John _S:
I drive my vehicles in excess of 40,000 hard miles a year and have put several hundred thousand miles on each. Use Amsoil in the engine, transmission and gear boxes and have never had a single maintenance issue.
Reviewed by Mose:
O put this oil 5w20 in a 2010 Ford Expedition,in march and it still looks clean great oil pressure,this is August👍
Reviewed by JCaba:
We use this oil in our Ford Fusion. We only put the best of oils in our vehicles and Amsoil makes an amazing product.
Reviewed by Dave:
I use this in my Ford car and will definitely buy it again the next time I need a case of it. Since switching to Amsoil I have been changing my oil at 25,000 mile intervals. I save money on oil changes not only by changing it myself but also on the extended change intervals.
Reviewed by Scott:
In all my vehicles
Reviewed by Larry:
Great product, I have been an avid user of Amsoil for more than 20 years now.
Reviewed by Tom:
I use this oil in my Dodge Hemi and change oil every 25,000 miles. It does not use any oil between changes and runs great.
Reviewed by Hammer 10:
Put in son's power equipment and all of a our Harley Davidsons plus our Roush Supercharged Pickup.
Reviewed by Chris:
Would buy again
Reviewed by Zig:
I find this oil to be worthy and the best of all oils. I can not believe that I put this oil in my 2005, Dodge Ram, 98000 miles, 4X4, Quad Cab, Hemi over 3000 miles ago, I just checked the oil and it still looks like the day I put it in. I used to have a little lifter tick, that went away and surprisingly I am getting a few miles better per. gallon, my truck simply runs smoother and quieter. Yes, this oil cost more, believe me my truck takes 7 courts, but I personally feel that if I can keep my truck for another 10 years for a little more now, then that is a big savings to me in more ways then one because, I like my truck, it still looks great and drives great, the best part is, it's paid off years ago and I don't see any reason to put myself in debt because I wanted to save a few bucks on oil.
Reviewed by BusDriverRick:
I like using an oil product that I can trust, and this is it. I get better gas mileage and feel like my engine produces more power. Amsoil is a proven product that has stood the test of time. Thank you for offering this to us.
Reviewed by Bluewater:
I think amsoil products are pricing themselves out of the market. My last order for oil and filters was over 800.00 dollars and while I love the product and the cars have lots of miles on them. Almost 75.00 for and oil and filter change is getting out of control!!!! Going to be looking for an alternative for my next purchase
Reviewed by Pete:
Fuel and H.P. Gains Noticeable after changing over to Amsoil... I'll never Run Anything Else in My F-150 again!
Reviewed by CR:
I did a complete inspection of my vehicle engine right when I bought it. There was no sludge in it. For the past 5 years I've been using only Amsoil in it and after an engine failure I opened the engine and discovered
industrial quantities of sludge in the oil pan, all throughout the engine, blocked lubrication ports, etc. Head gaskets were in perfect condition, there was no antifreeze present in the oil.
I won't be using Amsoil anymore and I'm switching my other vehicle to a different brand too.
Reviewed by Norman:
use it in 2008 ram hemi. good stuff. 5 star
Reviewed by Kersey52:
Oil and ea filters are high quality and worth every penny
Reviewed by Mark the pipeliner:
Since my 2004 F-150 called for 5-20 I have used where required. Is far superior to any other 5-20 oil I tried and burnoff and protection.
Reviewed by Tom:
My wifes 2011 jeep with 3.8L engine always used a little oil in between oil changes , I changed the oil and put the signature 5w20 synthetic in and after a few thousand miles I checked the expecting to add which was normal,to my surprise I didnt have to add any oil it was still on full. I am (was) an avid Mobile one customer and it never let me down but this latest finding impressed me and I have worked in maintenance all my life and I never thought anything could beat Mobile One (a new day in this garage)
Reviewed by Scooter:
Product was delivered on a very timely fashion. I go through the bother of ordering online because the product is the best.
Reviewed by TINY:
WORKS JUST GREAT IN MY ECOBOOST F-150. ENGINE LOVES IT AND SO DO I
Reviewed by Wayne:
I have been using this product since 1981 with excellent results.
Reviewed by todd:
best oil ive ever put in my car
Reviewed by MP:
I love putting the 5w-20 Signature series motor oil in my 2017 Jeep Cherokee. I trust it just like I trust the AMSOIL products I use in all my vehicles.
Reviewed by Johnny:
I've been using this product in my 2010 F150 sence in was new great product temp stays down in the heat of summer and easy starts in the brutal cold days in the hart of the winter.
Reviewed by gerald the dice dealer:
Since I had just purchased a seven year old car with 105,000 miles on it,and not knowing when any of the fluids were last changed. The dealer would not change any of the fluids before and after I purchased this vehicle stating that since the vehicle was not at the factory's recommended change interval (mileage wise) they refused to change any fluid.So, I took it upon myself and I proceded to change out ALL of the vehicle's fluid's.Saving myself hundred's upon hundred's of dollars doing the work myself. As it turned out I chose Amsoil products and even though its only been a month since I changed out these fluids I have NOT regreted my decision.I feel that these product's that Amsoil offer's are by far the best to use for your car...
Reviewed by Will:
Great products great customer service excellent shipping time overall great company
Reviewed by SwanyWI:
This oil has worked awesome in my wife's Jeep Compass. Gas mileage improved slightly and it starts great when it's cold also up in northern WI. We have 80,000 on and it uses no oil in changes.
Reviewed by Ty:
Stand behind Amsoil 100%
I'd put it in every vehicle I have but some leak so bad it would be to expensive.
I would NEVER run anything but Amsoil in a vehicle with good Engine and Transmission.
Reviewed by Easy:
I use this in 3 of our vehicles,all use same oil and amsoil oil filters.Basically change the oil once a year.Best stuff out there!!!
Reviewed by Big twin:
Use this in my 2003 honda accord. 220,000 miles and going strong. No worries
Reviewed by B:
Great fule mileage and consistent viscosity over 12,000 mile change interval in a 5.7 Hemi.
Reviewed by Shawn:
Everything i own that uses any type of oil gets amsoil.
Reviewed by Robert:
Awesome oil
Reviewed by Kaly:
I use my truck for work and personal time. I live in Toronto. Dealing with heavy traffic and temperaturea - 25 C at times, it takes a toll on the engine, very happy with the oil
Reviewed by Rick:
I use this oil in three of my vehicles and home generator. I have had nothing positive experiences with and definitely recommend it.
Reviewed by
Rick:
I use this oil in three of my vehicles and home generator. I have had nothing positive experiences with and definitely recommend it.
Reviewed by Ras:
Great product, excellent service
Reviewed by Todd:
Good value, once a year protection.
Reviewed by Dirty German:
I have used Amsoil Synthetic Motor Oils for years now. The engines I put it in have gone 10's of 1000's of mile further than others of the same make and models which friends have owned. The engines run cooler and run better. And I consistently get better fuel mileage. Simply Put, I'm Sold.
Reviewed by rdj519:
Changing oil 1 time a year and trusting amsoil to protect our investment. Thank you
Reviewed by JC:
This oil cause my engine to run cooler along with the great AMSOIL transmission fluid .
Reviewed by uncle richard:
I have used this oil in all my vehicles since 2006. I have a 2006 charger with 3.5 h/o it has 273,000 ; 2006 town and country 3.8 has 255,000; and a 2013 charger 3.6 pentastar which has 148,000 , which gets between 33 and 35mpg on the highway at 70mph. I change the oil filter and top off fluid at 12,500 miles on each vehicle. (High quality filters purchased from amsoil.)
Reviewed by Electrobent:
It seems to work. I have not analyzed any gasser oils yet but Amsoil was great in my diesels so I figure they can handle gasoline which is so much cleaner.
Reviewed by Nick:
For some reason, my gas mileage went down after putting this oil in my tundra. I reset the computer at every oil change. I was using Pennzoil 5w-20 and got 15.8 mpg over 5000 mile span. I am nearing 5000 mile mark on this Amsoil product and my mpg is at 15.0
Reviewed by Flaco:
Maintain all my cars with amsoil
Reviewed by BigdaddyMRI:
I use this product in my wife's new 2017 Hyundai. Since the break-in period is over, I now use the 5W-20 Signature AMSOIL in the vehicle. The gas mileage actually increased slightly, and the engine purrs now, which is a change from the break-in oil. I will continue to use this oil, without doubt.
Reviewed by Ant:
Used in a new Dodge Caravan and works great
Reviewed by Rob the Jeeper!:
I have been using AMSOIL since 2013, love the quality and what the brand stands for. I will not consider any other brand for my Jeep Wrangler. Thank you!
Reviewed by Tim:
Several years ago I was looking for a high quality full synthetic oil for my motorcycles and after I did a lot of research I decided to go with Amsoil. Since then I have become a preferred customer and I use Amsoil products in all my vehicles. I trust Amsoil products and I would recommend all their products.
Reviewed by G:
Love the extended oil change intervals, with no harm to the vehicles
Reviewed by billbob:
used products from1997 to today
Reviewed by PSM-0341:
I love the fact that AMSOIL allows the freedom from changing oil all the time.25000 mile oil is wonderful!Buy this product and simplify your life.
Reviewed by patriot:
Talking to a woman about oil is not easy, but a co worker and former mechanic was the one that got me started. I am glad he did. I have been using Amsoil oil for about 6 years and will not use anything else. I first bought it because i drive a lot of miles to work but now i work from home mostly and still use it. Amsoil has quality products!
Reviewed by Pete:
Great product because of the extended drain intervals that can sometimes go beyond their 25k recommendation. Just be sure to have an oil analysis done once in a while.
Canada
United States
I'll always buy this product
I've had Amsoil in my 2003 F-150 since I bought it in 2005 and still going strong, no smoke, no rattling. It's a product I always recommend