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 K-Mac: 
I only use American AMSOIL in all my vehicles. For this one, I use it in my 2005 Honda Fit 1500cc..
Reviewed by K-Mac:
I only use American AMSOIL in all my vehicles. For this one, I use it in my 2016 Nissan Caravan NV350.
Reviewed by Jeff:
I run Amsoil oil and filter in my Yukon Denali 15,000 miles between changes. Just reset the change oil message at 7500. Doing this for years with several GMC Yukon's. At 250,000 plus miles no oil burn at all. Very impressed with not having to go under the car twice as much.
Reviewed by Ricky:
Awesome cold start protection, and anti-wear lube, simply the best
Reviewed by Mustang Larry:
So far all is good.
Reviewed by Mustang Larry:
Why is it when I change my oil does my mileage drop by 2mpg. For the first 400 miles 1 1/2 to 2 mpg less then it creeps back up.
Reviewed by Ron the Tyrolian:
I have relied on Amsoil products for years to protect my engines and it has done exactly that.
Reviewed by SamLac:
I started using AMSoil in the mid 80s while in Alaska. Cold extreme make lubrication very critical. At minus 40, most petroleum lubes won't even drip off the dip stick and when started cold you can hear every bearing in the engine as there is little or no lube flowing. No so with my AMSoil.
Reviewed by Jeff:
I've been running 5W30 Signature Series in my 2002 Tacoma since putting it on the road in 2016 with 116,000 miles on the engine. I have since had Oil Analyzers (Amsoil, Inc.) test three samples from the truck so far, and have yet to have the oil last more than 13K miles before being told it's time for it to be changed. So much for the 25,000 miles/1 year claim...
Reviewed by Grizz:
I have 2 vehicles that have had this oil in them (changed every 15,000mi) since I bought them new. They both have mileage approaching 250,000, and they run like BRAND NEW. My newest vehicle is a 2017 Subie Forester Turbo so it gets Signature 5W-30 every 10,000 miles, and I'm sure it will see 200k and beyond.
Reviewed by GF1563:
Love the extended oil change intervals and my fuel mileage increased slightly, which leads me to believe it must be lubricating everything very well.
Reviewed by Pat:
It's great year round hot or cold
Reviewed by Don:
Several years ago I switched to Amsoil in my GMC Yukon. I was very impressed with what the Signature Series 5w-30 Motor Oil looked like after the first oil change. With all the oils and products that Amsoil offers, I have since switched everything I own over to Amsoil. Even my lawnmowers.
Reviewed by dhgguy:
Used in my F150 exclusively. Excellent oil & filter.
Would not use anything else.
Reviewed by Ronv:
I have used Amsoil for 30 years and wouldn't think of using any other oil.
Reviewed by Mister nice:
Love that you don't have to change oil as offer as regular oil. Is is a little high. Hey but you get what you pay for.
Reviewed by Henry:
I use Amsoil exclusively
Reviewed by Jblev77:
#1 for 3.5L ecoboost
Reviewed by Ed:
I like being about to change oil at any time between 5-10k and not have to worry about weather or not the oil is doing it job !!!
Reviewed by RebelnOhio:
I have been using Amsoil for over 15 years and have never had a problem, it's a well proven product that I trust in all of my cars for work and for pleasure. I will will continue to use Amsoil and benefit from it's proven results! I own a Livery/Limo Service and I drive about 40-50K miles a year on various cars and I believe Amsoil is the best Oil for all of my vehicles. With the long 15k Mile change intervals it is a money saving gem and your engine benefits 100%. I recommend there products highly!
Reviewed by KENT:
I've used this brand and series in my Dodge Ram 4.7 v-8 since I acquired it at 90,000 miles. I've driven another 70,000 miles since and the engine is stronger than it's ever been! I expect to drive this truck until at least 300K miles because of the Amsoil Signagture Series Synthetic brand motor oil. I won't use anything else!
Reviewed by KK:
I use Amsoil on my SUV and love it!
Reviewed by Tom:
I use ansoil on all of my trucks, motorcycles, ATVs. This oil I use on 2017 Hemi 2500. It cannot be beat.
Reviewed by G:
Instant satisfaction, after the first start up i could already hear and feel things running smoother.
Reviewed
by Redtundra8:
This is the best oil money can buy in my opinion. I use this in all my vehicles and have for the last 12 years. Love only having to change the oil once a year. I highly recommend this product.
Reviewed by Pat:
Bestboil products on the market by far. I run it in all my vehicles
Reviewed by Billy G:
I have used Amsoil products for many years in all of my vehicles and small engines. I have never had an issues. I recommend Amsoil even though it is not the cheapest but the delivery is very prompt.
Reviewed by Wingsprnt:
Not sure about the oW-20 weight here in Florida, but that is what Honda calls for.
Reviewed by Greg:
Always met my expectations.
Reviewed by MatsB:
Using Amsoil in all of my family's cars. Using Signature series in cars that drive over 12,000 miles per year, and XL series in cars that drive less than 12,000 miles.
Sent a 27,000 mile sample for testing to a independent lab, and they recommended 30,000 miles next time based on the excellent results.
Also using Amsoil in all lawn equipment and for a standby generator.
Reviewed by Robert Long:
Great product gives better fuel mileage and cleaner oil after changes
Reviewed by Tim:
I've been using Amsoil since the 1980s in everything with an engine. And have bragged about it's benefits to anyone who'd listen.
Reviewed by Rob:
I get better mileage with Amsoil
I run my 4x4 very hard and Amsoil is doing a great job of keeping it running strong
Reviewed by Elvis of Aragorn:
My 2004 Silverado (5.3L V8) has had a steady diet of Amsoil since its second oil change. I have stuck to the 10,000 mile interval, using Amsoil Ea filters & Signature Oil. She's about to roll over the 200,000 mile mark, and I have had no engine issues. I use Amsoil Signature Synthetic Oil in all of my vehicles, and plan on keeping it that way.
Reviewed by Pinto:
I'm city driving in a 4x4 Ford van and after my last oil change the oil was still in great condition after 15,000 miles. just used the cleaning solution so lets see how this improves engine longevity. really happy with all th products I have received.
Reviewed by S2kadi:
I use Amsoil Signature Series in both of my cars that are susceptible to burning oil. The 10W30 goes into my Honda S2000 and works great! Amsoil is the only oil I use in my motors and gearboxes, after trying out several different brands, I have found their quality to be of the best.
Reviewed by pro4100:
I use it in my Subie Forester and my silverado 1500. no problems ever!
Reviewed by Quick charge water:
Yeah like to 25,000 my old changed
Reviewed by Beast:
I will never use conventional again. 10K mile Oil changes, or once a year. You cant beat the quality and value of this product. No dealer or mechanic can ever persuade my to change every 3k miles again!. Get you some!
Reviewed by ScoobyVTEC:
Bought Amsoil for all of my cars so I wouldn't have to change the oil so frequently and for the protection it gives all of the internal moving parts. I've noticed an increase in MPG and smoothness when I drive.
2017 Civic Type R
2012 Pilot Touring AWD
1998 Civic EX
Reviewed by Kw:
Been using amsoil for 10 yrs would never use aNY other prout ever. Noticeable mileage increase and smoothness. I run the signature series 5/20. Amazing oil that's all I could say.
Reviewed by Jay:
I've used other upper end brands (Royal Purple, Mobil One, Pennzoil) and their performance can't compete with Amsoil. I'v been using Amsoil products exclusively for past 10 years and I am extremely satisfied with their products and their customer service. They are both excellent. Call center employees very knowledgeable about their products. I would definitely recommend their products above all others. Their commitment to quality and performance is second to none.
Reviewed by Tommy:
I've used this for 10 years since I bought my F150 5.4 with 50k miles.
This year I was returning from vacation and I noticed the truck seemed low on power. I brought it to my mechanic and he found 1 bearing gone on a roller rocker. Rocker shaft destroyed. 3 collapsed lifters and a broken in half cam chain tensioner. His only explanation as to why the engine still ran was the oil. He said Amsoil is Motor Magic.
We have a new engine now topped off with all Amsoil products!
Reviewed by Matt:
Amsoil is the only thing I will put in my Vehicles. Why waste Money on oil that could possibly reduce the lifetime of your engine? Spend the few bucks more and save money in the long term.
Reviewed by Scooby:
I use Amsoil in all that I own from vehicles, lawn equipment, generator and my motorcycle. Everything that I put it in runs great and the oil runs/ages very clean vs others I've tried. I use oem filters but with Amsoil the oil just doesn't seem to wear out like others if that makes any sense.
Reviewed by KMitchell:
I have used this oil for years. In my 06 Durango. It has over 230,000 miles and is still going.
Reviewed by Bob:
I use Amsoil for all my vehicles for years and continue to trust all Amsoil products
Reviewed by Don:
I've used Amsoil products for years. If you understand the product technical reports, You will use this oil and filter combination. Best for wear, cleaning and longevity I've ever found. Lubricity is second to none.
Reviewed by Bosman:
Use in both personal and now work vehicle. Can't go wrong with extended drain intervals, pays off fast.
Reviewed by Titanium Tim:
I have been using Amsoil products for over 30 years I believe they are the best
Reviewed by Az Wild Burro:
I use Amsoil on all engines large and small. Top in its Class
Reviewed by Joe123456:
I have been using this in my Taurus since I purchased it (and Amsoil products in general for many cars over many years). The stuff performs great. Comes out feeling as slippery as it did when it went in (unlike conventional oils).
Reviewed by Clipp:
I always do all fluid changes in our Jeeps, changed everything over to amsoil and have never encountered any problems.
Reviewed by Gimpy:
I have used Amsoil engine oil, gear lube, metal protection spray and foam air filters as well as oil filters for almost 4 decades thanks to a former neighbor who worked in the aerospace industry. He was my go to dealer.
The signature series
oil that I am using now has served me and my vehicle well and my vehicle oil sensor has boosted the remaining oil life expectancy quite a bit Vs. the factory oil mileage to percent of oil life remaining.
The color, transparency and odor is my visual test process when I change my oil to compare Amsoil to other oils.
I am a firm believer in "you get what you pay for" and Amsoil is worth every cent for long life and peace of mind in your vehicles maintenance.
Reviewed by icesysman:
I'm currently using your 5W-20 synthetic motor oil in a 2008 Toyota FJ Cruiser. Startability in sub-zero weather has been excellent.I've also noticed an increase in gas mileage, which is a definite plus. The engine runs quieter and smoother than it did with conventional motor oils. I will continue using Amsoil products until I'm no longer able!
Reviewed by Dienliv:
Bought a brand new 2017 Ford Explorer (NA 3.5L). After a couple thousand miles, I changed the oil over to Amsoil Signature Series, using Amsoil's filter as well. I've been changing the oil based on the in-dash oil life counter which gets to right about 10,000 miles for servicing. All has been working just fine so far at 25k.
Reviewed by Nordy:
Love the protection and convenience of 1 oil change a year.
Reviewed by Red:
A true company that stands behind their products and has the best costomer assistants ever.
Reviewed by LD423:
I have multiple vehicles and use it in all of them, worries end when using Amsoil.
Reviewed by Ice man:
Using my personal vehicle. Stands up to hot and cold temperatures well. I like longer intervals of oil changes
Reviewed by Shane.B:
I use Amsoil in everything I own that has an engine( mower, snowblower, generator, compressor, truck, and minivan). What sold me was during harsh cold winter months (-25 to -35 Celsius) my truck kinda turned over slow for the first turn of the engine before firing right up using conventional oil. Thought what heck let's see how it works with synthetic oil during the winter..... long story short I use it all year round and won't ever switch back.
Reviewed by Legs2:
Have been using
Amsoil for the past four years and I'm very satisfied. My cars even seem to sound better. Amsoil gives me peace of mind knowing my cars are functioning better.
It's worth the extra money just because it prolongs the life of the engines
Reviewed by Pops:
Started using Amsoil in 2004 but was skeptical about the advertising claims. I would change my oil and send off a sample to have it analyzed. The results always came back showing that the oil was still good. I use the Amsoil EA oil filters also an have complete confidence in my engine lubrication. I use Amsoil products in all of my vehicles transmissions, differentials, etc.
Reviewed by Legs2:
Have been using Amsoil for the past four years and I'm very satisfied. My cars even seem
to sound better. Amsoil gives me peace of mind knowing my cars are functioning better.
It's worth the extra money just because it prolongs the life of the engines
Reviewed by Sam the man:
This amsoil since I use it the car run as New and is millag. On gas saved me money it's a good oil for
Reviewed by Armando:
I've used this product from the time we bought our Honda Pilot, used at 69,000 miles. The SUV now has 238,000, with maintenance and Amsoil, we plan on seeing the odometer turn half a million miles. I truly believe in this product. For the cost, it well benefits buying the Signature series, not only is it quality oil, we get more miles per gallon, we also get peace of mind knowing our engine is free from sludge and getting properties that keeps the engine running at its best.
Reviewed by Ford:
Best oil out there. Very easy choice.
Reviewed by
Majwood:
This oil is long lasting and keeps on slipping!
Reviewed by slim:
very good product and knowledgeable people about their product.
Reviewed by Bud:
For maintenance oil changes.
Reviewed by Bill:
I have been using Amsoil oil and filters for at least 10 years and have never had a problem that was oil related. This oil has been used in my 2013 Explorer and now in my 2017 Explorer. Recommend it to all who will listen and I am not a dealer.
Reviewed by RebelnOhio:
I have been using Amsoil for over 10 yrs. now and I have never had a problem with anything. For my money, this is the best Synthetic Oil you can buy and got he longest distance between oil changes! I wouldn't use anything else in any of my Lincoln Town Car's, MKS's or Cadillac's. Once you do the research on Amsoil and the benefits your car will receive, I think you will be very satisfied as I have been for yrs.
Reviewed by Jake:
1-once-a-year oil changes, and the BEST-protection for your investment,!
PERIOD! need I have to explain anything else,..?
Reviewed by Chris Natole:
For vehicle engine longevity I don't mess with conventional motor oil any longer. Why even bother risking the heart of your vehicle.
Reviewed
by Dmonacols3:
I use Amsoil in every vehicle I own. With the extended drain intervals and excellent protection it is the lowest cost as well as the best oil you can use.
Reviewed by Steve:
I can definitely tell when I'm not using Amsoil. I can feel it in the engine.
When I do use it, the motor is smooth as glass at the stop lights, and I know
over time, the wear and tear on a motor is minimal with it's continued habitual use.
I use it on all three of my vehicles. I've used other full synthetics in the past, but I can
tell the difference. AMSoil is superior. I feel it's
worth the extra money to me.
Reviewed by V8'er:
No problems are always a good thing. I've used this for the last 80K miles and have experienced no concerns. If a problem occurs, I will be concerned about the cause, until then I like this oil.
Reviewed by Jim Mc:
I've been using Amsoil for 20yrs. I believe it reduces wear and increases the longevity of my vehicles
Reviewed by Mike:
Excellent product, if u love your vehicles and want them to last a long long time, but Amsoil for them!! They deserve it.
Reviewed by Mrdoow:
When my free dealer oil changes ran out I switched to Amsoil on our Mazda CX-5. Average mpg on dealer oil was 22 to 24 according to the car's computer. On our first trip after changing to Amsoil, the average mpg readout went to 28-29. We had a couple of 32 mpg's on this trip also. AND BONUS, I only change oil once a year now. Great product.
Reviewed by Stan the Man:
Use mainly in class 8 trucks, expensive but good product I believe
Reviewed by peterj59efi:
once a year oil changes whats better than that
Reviewed by JW:
I use only Amsoil in every engine I own. My F150, the wife's Lincoln, the Harley, The Boss Hoss, My Shelby, My vintage Ford tractor (Z-Rod)The Toro zero turn My 1981 Briggs and Straton edger and anything else that stops by my home.
Reviewed by Lou:
As a do it yourself auto maintenance gear head, I value the peace of mind knowing I am using the best oil available for extended drain intervals.
Reviewed by Steve S.:
Switched to 5W-20 Amsoil Signature Series at my first oil change in my new truck & immediately noticed how quiet the engine runs along with an increase in fuel economy. Being a true full synthetic, it is the only oil I trust for the service demands of my truck & SUV. Thanks for a great product & service!
Reviewed by Dahanny:
This oil in my truck Hemi 5.7 2017 run perfect !
Reviewed by Moe:
Best oil on market use it in all my vehicles for years no issues
Reviewed by Rick:
Amsoil products are everything Amsoil say they are. They are simply the best and most effective products of their types, regardless whether it's oil, additives, etc...
While conventional oils can be good and do what you need it to, they just don't compare to Amsoil synthetic lubricants. They can't. That's the whole reason synthetic lubricants were developed in the first place.
When turbine engines were in development, conventional lubricants would completely fail. Engines would literally come apart...catastrophic
failure.
I've run Amsoil in every car I've had. I change it once a year; reduced waste, superior protection and longevity, lower cost.
It's a no-brainer.
Reviewed by Dan:
I drive my cars like I stole them. Pull a fifth wheel trailer coast to coast with my truck. Never had an engine failure or any engine or transmission problems.
Reviewed by Under/over:
We use your product in our (2) cars and our 2500 truck. After burning the oil in our transmit ion in a previous
motor home, we switched to AMS andhad NO further oil problems .
Reviewed by Trey512001:
25000 miles with a warranty! Incredible but thanks Amsoil
Reviewed by Mike:
Just one oil change in a year.
Reviewed by Mike:
Just one oil change in a year.
Reviewed by Bill:
The oil doesn't break down, does not lose his lubricity over a long period of time awesome motor oil
Reviewed by Father Bob:
My mechanic says that the Amsoil 5W-20 oil and filter is the best thing, other than keeping the car clean, that I can do for my Charger. I agree with my mechanic.
Reviewed by Mustang Mike:
Great product, towing & severe duty.
Reviewed by Mark:
Amsoil worked best in my last diesel so continued to use it in my new gas burner F250. Can't beat the quality, prices and timely delivery of your order either, I always receive it within two days of placing. As costly as vehicles are these days why cut corners on your oil. Amsoil is in all my vehicles and equipment.
Reviewed by Amie:
The Signature Series Motor oil is an effective product that makes you vehicle run better and last longer even if you are not as caring for it that you can be.
Reviewed by Florin:
I simply use AMS OIL in all my cars and don't look elsewhere. Never had a problem, all engines work like new, no worries.
You want the best, look
no further.
Canada
United States
A Trusted Product
I have been using Amsoil products in my vehicles and motorized equipment for many years and relay on its quality. As a "gearhead", I know how important using quality motor oils and greases are to machinery. They are my first choice for lubrication fluids.