Amsoil vs Mobil 1: Which
Synthetic Oil Rules the Road?
SHOP BY EQUIPMENT
SHOP MOTOR OIL
SHOP FILTERS
Have you ever wondered which motor oil truly delivers maximum engine protection? To find out, I went straight to the automotive aisle to investigate the leading synthetic brands. I checked the back of almost every quart bottle for its recommended oil change interval. To my surprise, most brands don’t commit to a specific mileage limit on the bottle—except for two industry giants: Amsoil and Mobil 1.
Amsoil vs Mobil 1
When you look at the guaranteed protection limits, the numbers speak for themselves:
- Mobil 1 Synthetic Oil: offering protection for up to 15,000 to 20,000 miles.
- Amsoil Signature Series: Takes endurance to the next level, offering a guaranteed protection interval of 25,000 miles or up to one year (under normal operating conditions).
While Mobil 1 is a good premium choice, Amsoil Signature Series pushes the envelope for drivers who want the ultimate long-drain performance and fewer oil changes per year.
Since 1972…Amsoil has pioneered the 25,000-mile oil change. One important rating of an oil is the“Total Base Number.”
Comparing Motor Oil TBN … Testing.
The higher an oil’s TBN, the better its ability to neutralize contaminants such as combustion by-products and acidic materials.
Higher TBN oils neutralize a greater amount of acidic material, which results in longer oil life and cleaner engines.
TBN levels decrease as the oil remains in service. When the level reaches a point where it can no longer protect against corrosion, the oil must be changed.
AMSOIL Signature Series is fortified with a heavy treatment of detergent additives. It delivers 30% more acid-neutralizing power than Mobil 1, and 36% more than Royal Purple, helping engines to stay cleaner, longer.
So, how good is Amsoil? Click on my “930,000 Mile Engine Teardown Brochure” and see how squeaky clean Amsoil kept my engine, changing the oil and filter every 20 – 25,000 miles. Get more test results here.
What This Means for Your Engine
- Higher TBN — longer oil life and a cleaner engine
- TBN – Amsoil 12 Mobil1 9
- Lower viscosity loss — stronger protection under heat
- Viscosity – Amsoil 11% Mobil 1 20%
- Amsoil leads both tests — measurable advantage in long‑term engine protection
Bottom Line
If you want an oil that lasts longer, protects better under heat, and maintains its viscosity, Amsoil Signature Series is the clear winner.
What Are the Ingredients In Your Oil?
While investigating the motor oil on the shelf, I found only two bottles that had the “oil change mileage” labeled.
However, none of the bottles listed the ingredients, including Amsoil and Mobil 1. Do you not find it amazing?
Most companies label their product ingredients, but when it comes to motor oil…none…zero. So you might say, it’s just oil that has been refined from crude oil.
Well, that’s partially true; however, the American Petroleum Institute has labeled these different types of oils. Now here’s where the rubber meets the road.
Secrets the Oil Companies
Don’t Want You To Know
Oil companies don’t want you to know how they cook up their “tested best” motor oils. If so, they would put the ingredients on the bottle, right?
Let’s take a closer look at the four types of oil being used to formulate their products. Here they are.
- Group I base oil…very cheap
- Group II base oil…cheap
- Group III base oil…better
- Group IV base oil…best (100% synthetic)
Which oil would you rather have in your equipment? Hang in there with me…you’re getting educated about motor oil.
How Can Amsoil Guarantee
Its Oil for 25,000 Miles?
From the information I have researched, Amsoil uses Group IV Base Oil, 100% synthetic oil, in their Signature Series (25,000-mile) oil. They add all the additives needed to go 25,000 miles or one year, whichever comes first. No need to add additives.
The Amsoil Extended-Life (20,000-mile oil) Synthetic oil has fewer additives, and the Amsoil OE Synthetic Oil (change at regular OEM requirements) has fewer additives. However, they are still 100% synthetic.
Now I think they’re telling me the truth because I drove my 99 Chevy van over 930,000 miles, changing the oil and filter every 20 – 25,000 miles until a valve keeper wore out that was not oil-related.
Amsoil has 100% Synthetic High-Mileage Motor Oil for vehicles with over 75,000 miles (good for 12,000 miles).
If You Think Your Oil Is So Good… Think Again!
Group II and Group III Base Oil stocks derived from petroleum oil are much cheaper. The oil companies will not tell you what “Base Oil” they’re using. I had to research what “Wikipedia” and “The American Petroleum Institute” had to say.
Most oil companies are likely blending Base II and Base III oils. Several oil companies may blend up to 30% of Group IV base oil stocks in their petroleum oil…making it a watered-down ”synthetic blend. In my opinion, a waste of money.
I’m speculating that some companies use a small amount of Group IV along with the GTL Group III (highly refined mineral oil) in their high-mileage oil.
However, since this new GTL Group III oil has been given the okay by the API to be called synthetic, they may have deleted the Group IV to cut costs.
Molecules In Your Oil…
Can They Take The Heat?
Here’s an illustration of the molecular structure of Group II & III base oil. Fill a barrel with all different sizes of balls…basketball…baseball…softball… golf ball…tennis ball…football.
Then try to reach the bottom of the barrel. There’s less consistency in the molecular structure of the oil.
When the oil heats up…all these different sizes of molecules can’t possibly work together to lubricate the metal surface efficiently.
The molecules eventually exhaust themselves…break down and have to be disposed of…or the oil has to be changed more often.
Reduce Friction…Spike Lubrication
Group IV base oils…100% synthetic…the molecules are all consistent. When the molecules are all the same size, there’s a dramatic reduction in friction and a spike in lubrication.
For example, fill a barrel with all ping-pong balls. Then try to reach the bottom of the barrel. That pretty much describes the molecular structure of Group IV oils.
Yes, they’re more expensive; however, you’ll end up paying less due to fewer oil changes, increased fuel mileage, and fewer repairs.
Conclusion…Getting beyond what you think!
Hopefully, I’ve shed some light on your deeply ingrained imagination about the possibility the oil you’re presently using…if not a “Group IV base oil”… is not the best oil!
You cannot escape the facts. There are cheap oils…Base II… there are better oils…Base II & III mixed… There are good oils, Base III, and there are great oils…Base IV.
AI Compares Amsoil vs Mobil 1
Summary of Amsoil vs Mobil 1
How can you really tell which is better when it comes to Amsoil vs Mobil 1? It all has to do with additives and testing.
Mobil 1 “Annual Protection synthetic oil” may take you up to 15 – 20,000 miles on an oil change.
Amsoil Signature Series synthetic oil will take you up to 25,000 miles on an oil change. And the “slam dunk” is they have the nanotech 15K and the 25K mile oil filters to go with it.
Before I switched over to Amsoil, my imagination was at war with my brain.
There’s no way oil can last 25,000 miles. I have an expensive investment. I’m concerned that my engine will sludge up. Don’t take the chance. You can still change your oil every 5,000 miles.
But what if the oil is as good as what I’m hearing and reading? Wouldn’t that be incredible if I could go 25,000 on an oil change?
That would mean only 4 oil changes a year instead of 20. (I was driving 100,000 miles a year) What the heck…I’m going to give it a try.
My First Oil Change and
Oil Analysis with Amsoil
May of 2000, at 68,250 miles on my 99 Chevy van, I added Amsoil synthetic OW-30 Signature Series oil to my 350 engine.
While pouring the oil into the filler tube, I noticed on the back of the bottle…good up to 35,000 miles! Now today it says on the front of the bottle…Guaranteed 25,000 Miles.” It no longer has the 35,000 miles on the back.
Can you imagine what I thought whenever I saw that? Yep…you’re right. Are they crazy?
Changing my oil from 5,000 miles to 25,000 miles was a big stretch for me. But 35,000 miles, that was a go-or-no-go moment!
Something said between my ears…go ahead…try it…let’s see if this oil will go 35,000 miles.
Catch A Sample Of Oil
I got to thinking, if I could catch a sample of the oil when changing it at 35,000 miles, something I’d never done before, and had it analyzed…that would settle the score.
Great idea, John. I checked to see if Amsoil had an oil analysis kit…and they did.
It was August of 2000…at 103,750 miles (35,500 miles on the oil)…I drained the oil (yes, it was black)…caught a sample and sent it into Amsoil.
A week later, with the report in hand, I called Amsoil to review it with me.
Your Oil Is Good For Another 10-15,000 Miles
To my amazement, this is what they said, ” Your oil is good for another 10-15,000 miles. Just change the oil filter!!”
I asked him twice…Would you repeat what you just said?
The reason I was in disbelief…the downside of a delivery service: lots of idle time. Sitting and waiting to pick up another delivery.
I most likely had a couple hundred hours of idle time on the oil, running the AC during the summer months, June, July, and August.
From what I have read, the car manufacturers estimate each hour of idle time is equivalent to 25-35 miles of driving.
In the heat of the summer, I would idle the engine with the AC running to cool the inside of the vehicle, and in the wintertime, I would idle the engine with the heater running to warm the inside of the vehicle.
Due to so much idle time, I felt more comfortable changing the oil and filter at 20 – 25,000 miles over my “Million Mile Journey.”
Amsoil…Like Aspirin
One thing that caused me to lean toward Amsoil was pain. The pain of changing my oil every two weeks. I call it the 5,000-mile headache.
Amsoil is like aspirin. It did away with my oil change headache, and put an extra $2000 in my pocket each year!
You can order online and have the product shipped to your doorstep in 2-3 business days.
Contact your dealership or local repair shop to change your oil and add the Amsoil synthetic oil and filter to your engine. And just that quick…you’re up and running.
Buy Amsoil Synthetic Oil At Wholesale Price
Amsoil Synthetic Oil:
- Allows your engine and transmission to float on a layer of lubrication
- Keeps your engine and transmission squeaky clean
- Prevents sludge and varnish build-up
- Increases fuel mileage by 4-6 percent
- Increases engine horsepower by up to 6 percent
- Extreme Cold Protection…Amsoil remains fluid up to -50 below
- Fewer repairs and maintenance
- Lower emissions
- Less waste oil
- A cooler-running engine, transmission, and differential
And for you…a fatter wallet and peace of mind!
Happiness Is A Quick-Starting Vehicle At -20 Below…Amsoil Synthetic Oil Pours at -50 Below
Have questions? Need help selecting the right oil and filters for your vehicle or equipment?
Feel free to contact me anytime at (937) 417-1127 or jbs777@gmail.com. If you reach my voicemail, leave a message or text, and I’ll respond as soon as possible.
Happy Trails
John Schlimmer
Independent Authorized Amsoil Dealer
www.MillionMileChevy.com
PS…Most Japanese models take the Ea15K oil filter…good for 15,000 miles.
If you drive over 15,000 miles a year…change the oil filter…no need to change the oil until 25,000 miles or one year.
European cars … oil and filter need to be changed at the recommended mileage by the owner’s manual.
