AMSOIL vs Mobil 1
Team Owner
Joined: Mar 2001
Posts: 25,889
Likes: 7
From: Virginia Beach
CI 3-5-6-7-8 Veteran
I've been running the Mobil in the car in various weights 5w30 to 0w40 for the car's whole life now at 35,xxx thousand miles.
I run the car very hard and I don't see how switching the Amsoil will gain me anything...
I mean Mobil 1 0w40 is the best Mobil oil made and I'm pretty sure it's protecting my car just fine.
I run the car very hard and I don't see how switching the Amsoil will gain me anything...
I mean Mobil 1 0w40 is the best Mobil oil made and I'm pretty sure it's protecting my car just fine.
Le Mans Master
Joined: Aug 1999
Posts: 5,411
Likes: 2
From: N Carolina 08 Z51 Coupe
Originally Posted by Cobra4B
I've been running the Mobil in the car in various weights 5w30 to 0w40 for the car's whole life now at 35,xxx thousand miles.
I run the car very hard and I don't see how switching the Amsoil will gain me anything...
I mean Mobil 1 0w40 is the best Mobil oil made and I'm pretty sure it's protecting my car just fine.
I run the car very hard and I don't see how switching the Amsoil will gain me anything...
I mean Mobil 1 0w40 is the best Mobil oil made and I'm pretty sure it's protecting my car just fine.
Unless you are pushing your car to its limits for extended periods, Mobil-1 is all you ever need. Easy to get and priced right.
If you are into full time racing or extended heavy use, then the benefits of Redline, Amsoil makes sense.. Mobil-1 has been improving ever since its introduction into the market. When it first came out it did not use a quality base stock and was not a full synthetic. M1 has come a long way and is now a quality synthetic oil. For the majority of C5 owners out there, M1 is more than enough protection.
mike
Race Director
Joined: May 2001
Posts: 15,324
Likes: 2,077
From: Guelph, Ontario
I agree that Amsoil 0w30 is their best choice. A lot of people get turned off by it's higher price though, since their 5w30 is cheaper. The biggest benefit of Amsoil 0w30 (over their 5w30) is that it's designed to go even longer intervals, but most people don't even push Amsoil 5w30 to it's limit anyhow. The wear numbers between those two oils when run for under 5-6k is about the same (except in winter where the 0w30 would be a lot better)
Thread Starter
Premium Supporting Vendor
Joined: Aug 2001
Posts: 5,364
Likes: 38
From: King George VA
Originally Posted by mfrnka
I'd like to compare apples to apples and have never seen anyone mention pricing specifics. How much for a quart of Amsoil motor oil?
Keep in mind that for $10 you can sign up as a Preferred Customer (for six months) and buy the oil at about 20% less. You can do this by calling 1-800-777-7094 and using reference #1206638 or by going here and using the same reference number:
AMSOIL Preferred Customer Program
I will say that as a dealer (same pricing as Preferred Customer), I can have AMSOIL 5w30 shipped to my door for about the same price as it costs me to buy Mobil 1 at the store.
__________________
C66 Racing #66 NASA ST2, SCCA T2
AMSOIL Dealer (Forum Vendor)
AMSOIL Preferred Customer Program (Members buy at Wholesale - a savings of about 25%)
C66 Racing #66 NASA ST2, SCCA T2
AMSOIL Dealer (Forum Vendor)
AMSOIL Preferred Customer Program (Members buy at Wholesale - a savings of about 25%)
Racer
Joined: Mar 2004
Posts: 401
Likes: 0
From: Sterling Heights MI
99.99% of drivers would be fine with Mobil 1, or Red Line. For the price Mobil 1 is hard to beat. Who really needs to extend the life of engine oil past Mobil 1's limits anyway? I don't know many C5 drivers putting 10K miles on a year.
Race Director
Joined: Jan 2002
Posts: 14,185
Likes: 286
From: Shitcago IL
St. Jude Donor '04-'05-'06-'07-'08
Haven't changed the oil in my C5 yet, but I think I will go with Amsoil with my next oil change. Is there anyone in the Chicago area that sells it or would I have to purchase it on the net.
Corvette Stories
The Best of Corvette for Corvette Enthusiasts
Top 10 Most Expensive Corvettes Ever Sold on Bring A Trailer
Brett Foote
10 Things Every Corvette Owner Needs (2026 Edition)
Michael S. Palmer
8 Most "Only Corvette Owners Understand" Quirks and Problems
Pouria Savadkouei
10 Reasons the C6 Z06 is Still A Performance Benchmark After 20 Years
Joe Kucinski
How Much Horsepower Every Corvette Engine "LOST" in 1972
Joe Kucinski
Top 10 DOs and DON'Ts for Protecting Your Convertible Top!
Michael S. Palmer
Top 10 Most Explosive Corvettes Ever Made: Power-to-Weight Ratio Ranked!
Joe Kucinski
150 hp to 1,250 hp: Every Corvette Generation Compared by the Specs That Matter
Joe Kucinski
8 Coolest Corvette Pace Cars (and Replicas) of All Time
Verdad Gallardo
Pro
Joined: Mar 1999
Posts: 535
Likes: 1
From: GA
Originally Posted by Subdriver
I'd love to quote you a price, but AMSOIL's prices are set by AMSOIL and dealers aren't allowed to modify them so as to keep the big dealers and the small ones on a level playing field. You can easily check prices by clicking the AMSOIL link to the left and check pricing on the products you are interested in.
Keep in mind that for $10 you can sign up as a Preferred Customer (for six months) and buy the oil at about 20% less. You can do this by calling 1-800-777-7094 and using reference #1206638 or by going here and using the same reference number:
AMSOIL Preferred Customer Program
I will say that as a dealer (same pricing as Preferred Customer), I can have AMSOIL 5w30 shipped to my door for about the same price as it costs me to buy Mobil 1 at the store.
Keep in mind that for $10 you can sign up as a Preferred Customer (for six months) and buy the oil at about 20% less. You can do this by calling 1-800-777-7094 and using reference #1206638 or by going here and using the same reference number:
AMSOIL Preferred Customer Program
I will say that as a dealer (same pricing as Preferred Customer), I can have AMSOIL 5w30 shipped to my door for about the same price as it costs me to buy Mobil 1 at the store.
Thanks for the info, very helpful.
Thread Starter
Premium Supporting Vendor
Joined: Aug 2001
Posts: 5,364
Likes: 38
From: King George VA
Originally Posted by DanielW
Haven't changed the oil in my C5 yet, but I think I will go with Amsoil with my next oil change. Is there anyone in the Chicago area that sells it or would I have to purchase it on the net.
I'm sure there are a bunch of AMSOIL dealers in Chicago, but a quick note before I tell you how to find one. I am a supporting forum vendor and sales bought via my dealership go to support this site. You can buy via my dealership by either calling 1-800-956-5695 and using reference #1206638, or by using the AMSOIL link to the left which should automatically tag you as customer 1206638, but if it doesn't you can always enter that customer number manually. Also note that AMSOIL sets retail prices so no dealer should be undercutting any other, meaning a local guy will sell it for the same price as via the above number or link.
That said, I'm happy you are willing to try AMSOIL even if it doesn't benefit my race team or this site, so here you go:
Locate Your Nearest AMSOIL Dealer
Note: I would appreciate if you put referral #1206638 in the appropriate block. Thanks.
Thanks for the info, very helpful.
The oil debate, again
Almost as bad as the "Which is faster, the A4 or MN6?"
Almost as bad as the "Which is faster, the A4 or MN6?"
But since you asked, MN12... oh wait, that wasn't one of your choices.
I don't know many C5 drivers putting 10K miles on a year.
AMSOIL Product Change Interval Guide
Last edited by C66 Racing; Jul 15, 2004 at 03:29 PM.
Uh, oh! Here we go again! 
Melting Slicks
Joined: Sep 2003
Posts: 2,669
Likes: 5
From: Florida Gulf Coast
St. Jude Donor '05-'06-'10-'11
Just curious. Does anyone know if switching to Amsoil will help to quiet down the infamous piston slap in a low mileage 2002 motor ?
It does quiet down after warm up. Have always used the Mobil 1 in it so I don't know myself.
and on a lighter note.......the MN6 is only faster if you also have BSM's and are using Zaino.
It does quiet down after warm up. Have always used the Mobil 1 in it so I don't know myself.
and on a lighter note.......the MN6 is only faster if you also have BSM's and are using Zaino.
Melting Slicks
Joined: Oct 2000
Posts: 2,409
Likes: 0
From: Brentwood Tennessee
Cruise-In II Veteran
Cruise-In III Veteran
While I believe that Mobil 1 is an excellent lubricant, and may be the best of the major brands available at your favorite auto store, I also want to share some independent lab tests that show it isn’t necessarily the best lubricant on the market.
Comparative Oil Test
AMSOIL vs Mobile 1 Oil Test
AMSOIL 100% Synthetic 5w30 Motor Oil is formulated with advanced Polyalphaolefin (PAO) synthetic base stocks. PAO base stocks are the industries premier base stock technology, and when combined with an exact blend of premium additives, provide second to none protection and performance in the most demanding operating conditions.
Why AMSOIL?
•First to develop an API-rated 100 percent synthetic motor oil.
•First to introduce the concept of "extended drain intervals" with a recommended 25,000-mile/1-year drain interval.
•First U.S. company to utilize the NOACK volatility test as a standard of performance excellence.
•First to produce synthetic motor oils for diesel engines, racing engines, turbo and marine engines.
•First to introduce synthetic oils that legitimately contribute to improving fuel efficiency.
•First to manufacture synthetic gear lube for automotive use.
•First to manufacture a 100:1 pre-mix synthetic 2-cycle oil.
•First to manufacture a synthetic automatic transmission fluid for automotive use.
AMSOIL’s extended drain intervals actually save money (and obviously time):
Cost Savings of Longer Drain Interval
AMSOILs actual recommended drain intervals can be found here:
AMSOIL Product Change Interval Guide
While I understand many of us are resistant to the time honored 3 months or 3000 mile change interval, the industry is slowly coming to see the benefits of extended drain intervals. AMSOIL is leading the effort with their high quality synthetics. However, GM appears to be the first major automobile corporation to be embracing this philosophy with the oil life system calculator in its vehicles. AMSOIL’s lubricants have been formulated to address the trade-offs involved with extended drain intervals as the above comparison information shows.
Motor Oil Drain Intervals: An Ethical Burden?
Buy AMSOIL at Wholesale
AMSOIL Preferred Customer Program allows you to buy any AMSOIL product at wholesale, which is about 15-20% less expensive than retail. Cost is $10 per six months and you can buy as much oil as you want during that six months. To sign up, all it takes is one phone call to 1-800-777-7094. Give them reference number 1206638.
Or you can use this link:
AMSOIL Preferred Customer Program
Again, please put 1206638 in the customer number block.
While I understand many (most?) of you will probably never use AMSOIL in your Corvette as GM recommends Mobil 1, I would appreciate it if you would consider trying AMSOIL in your other vehicles. AMSOIL makes products for almost every type of machinery that has an engine, from cars to diesels, to farm equipment, to snowmobiles, watercraft, ATVs, etc, including lubricants, appearance products, oil filters, air filters, spark plugs (Bosch), wiper blades (Bosch), etc. More information on the full AMSOIL product line can be found on their corporate homepage:
AMSOIL Corporate Homepage
Own a business?
AMSOIL has two programs that may benefit your business.
Retail Sales Program
If you own a business a retail business with no more than 12 retail outlets that sells products "off the shelf", you may buy AMSOIL products at wholesale and sell them at retail, keeping the profits.
Commercial Program
If you own a business that uses lubricants, such as a vehicle fleet of cars, trucks, farm equipment, recreational vehicles, etc, you may buy AMSOIL products at wholesale and use them for your business.
Both of these programs involve no cost to start. Several forms are required to register your business account with AMSOIL. If you are interested, please contact me at c66racing@hotmail.com and I will provide you with more information.
Thank you for your consideration and support.
Comparative Oil Test
AMSOIL vs Mobile 1 Oil Test
AMSOIL 100% Synthetic 5w30 Motor Oil is formulated with advanced Polyalphaolefin (PAO) synthetic base stocks. PAO base stocks are the industries premier base stock technology, and when combined with an exact blend of premium additives, provide second to none protection and performance in the most demanding operating conditions.
Why AMSOIL?
•First to develop an API-rated 100 percent synthetic motor oil.
•First to introduce the concept of "extended drain intervals" with a recommended 25,000-mile/1-year drain interval.
•First U.S. company to utilize the NOACK volatility test as a standard of performance excellence.
•First to produce synthetic motor oils for diesel engines, racing engines, turbo and marine engines.
•First to introduce synthetic oils that legitimately contribute to improving fuel efficiency.
•First to manufacture synthetic gear lube for automotive use.
•First to manufacture a 100:1 pre-mix synthetic 2-cycle oil.
•First to manufacture a synthetic automatic transmission fluid for automotive use.
AMSOIL’s extended drain intervals actually save money (and obviously time):
Cost Savings of Longer Drain Interval
AMSOILs actual recommended drain intervals can be found here:
AMSOIL Product Change Interval Guide
While I understand many of us are resistant to the time honored 3 months or 3000 mile change interval, the industry is slowly coming to see the benefits of extended drain intervals. AMSOIL is leading the effort with their high quality synthetics. However, GM appears to be the first major automobile corporation to be embracing this philosophy with the oil life system calculator in its vehicles. AMSOIL’s lubricants have been formulated to address the trade-offs involved with extended drain intervals as the above comparison information shows.
Motor Oil Drain Intervals: An Ethical Burden?
Buy AMSOIL at Wholesale
AMSOIL Preferred Customer Program allows you to buy any AMSOIL product at wholesale, which is about 15-20% less expensive than retail. Cost is $10 per six months and you can buy as much oil as you want during that six months. To sign up, all it takes is one phone call to 1-800-777-7094. Give them reference number 1206638.
Or you can use this link:
AMSOIL Preferred Customer Program
Again, please put 1206638 in the customer number block.
While I understand many (most?) of you will probably never use AMSOIL in your Corvette as GM recommends Mobil 1, I would appreciate it if you would consider trying AMSOIL in your other vehicles. AMSOIL makes products for almost every type of machinery that has an engine, from cars to diesels, to farm equipment, to snowmobiles, watercraft, ATVs, etc, including lubricants, appearance products, oil filters, air filters, spark plugs (Bosch), wiper blades (Bosch), etc. More information on the full AMSOIL product line can be found on their corporate homepage:
AMSOIL Corporate Homepage
Own a business?
AMSOIL has two programs that may benefit your business.
Retail Sales Program
If you own a business a retail business with no more than 12 retail outlets that sells products "off the shelf", you may buy AMSOIL products at wholesale and sell them at retail, keeping the profits.
Commercial Program
If you own a business that uses lubricants, such as a vehicle fleet of cars, trucks, farm equipment, recreational vehicles, etc, you may buy AMSOIL products at wholesale and use them for your business.
Both of these programs involve no cost to start. Several forms are required to register your business account with AMSOIL. If you are interested, please contact me at c66racing@hotmail.com and I will provide you with more information.
Thank you for your consideration and support.
Pro
Joined: Jun 2012
Posts: 633
Likes: 0
From: Van Buren Arkansas
Well, since this has been revived, I'll throw in my experience with Amsoil. My transmission shifted fine, it was a little notchy but nothing bad, but it was a little noisy, you could hear the synchro's a tad bit, just normal 90,000 T56 stuff lol. I saw Toque's writeup and decided to give Torque Drive a shot. Since I was already doing the transmission I figured it'd be a pristine time to do the rear differential as well since the car was going up. After the fluid change the notchyness in my transmission was gone and the sychro's and everything in the transmission were dead silent, made a world of difference, especially cold shifting. The rear diff fluid was an easy change too, I just did it because I was there and the car had 90,000 miles on it, my diff never made noise or anything before though. The only fluid I hadn't switched over to Amsoil was my actual motor oil, as the car had Mobil 1 its entire life and it just felt sacrilegious to go to something else. I finally decided to order some Amsoil Signature Series 5w30 from ^C66 Racing and it came in the mail two days ago. I changed it yesterday and no longer does my car sound like a sewing machine! This has been the best fluid I've used in any vehicle of mine and I will continue to use it from here on out.
Melting Slicks
Joined: Jan 2009
Posts: 2,127
Likes: 33
From: Easley/Anderson South Carolina
Thread Starter
Premium Supporting Vendor
Joined: Aug 2001
Posts: 5,364
Likes: 38
From: King George VA
Well... in 2004 when I started this thread I can't remember if it was or wasn't. 
They had the XL line about that time and not sure when they got that line API starburst certified.
Today, these two lines are API Starburst Certified (come in other viscosity grades as well):
AMSOIL XL Synthetic 5w30 (Product Code XLFQT)
AMSOIL OE Synthetic 5w30 (Product Code OEFQT)
Their top tier Signature Series oil is not API Starburst Certified. AMSOIL feels the cost and constraints on API Starburst Certification are not justified for this series of oil. Starburst certification is very expensive, a cost that has to be passed to the consumer. The certification puts strict limits on transferability. If you buy PAO basestock from company X, they raise prices, so you switch to buying PAO basestock from company Y, your certification is lost and you have to do it again (more costs). That said, the Signature Series meet API SN specification and AMSOIL carries their own warranty on their fluids:
AMSOIL Corporate Warranty
More than happy to get AMSOIL products for forum members at dealer wholesale pricing, about 25% below retail, via the AMSOIL Preferred Customer Program. Drop me a PM if interested.
They had the XL line about that time and not sure when they got that line API starburst certified.
Today, these two lines are API Starburst Certified (come in other viscosity grades as well):
AMSOIL XL Synthetic 5w30 (Product Code XLFQT)
AMSOIL OE Synthetic 5w30 (Product Code OEFQT)
Their top tier Signature Series oil is not API Starburst Certified. AMSOIL feels the cost and constraints on API Starburst Certification are not justified for this series of oil. Starburst certification is very expensive, a cost that has to be passed to the consumer. The certification puts strict limits on transferability. If you buy PAO basestock from company X, they raise prices, so you switch to buying PAO basestock from company Y, your certification is lost and you have to do it again (more costs). That said, the Signature Series meet API SN specification and AMSOIL carries their own warranty on their fluids:
AMSOIL Corporate Warranty
More than happy to get AMSOIL products for forum members at dealer wholesale pricing, about 25% below retail, via the AMSOIL Preferred Customer Program. Drop me a PM if interested.
Instructor
Joined: Feb 2005
Posts: 219
Likes: 0
Amsoil is good motor oil but not better than Mobil 1. Amsoil is actually often being on additive technology. Look at a virgin oil analysis of Amsoil and Mobil 1 and you'll see that Amsoil looks very similar to Mobil 1 from 2006. They are still using the overbased calcium at 3,000 ppm + levels. Mobil's latest SN formulations are lower SA at .8.
Amsoil relies on bench tests which are often not that good at demonstrating oil superiorority. Amsoil is very good oil, but not better than Mobil 1, Pennzoil Platinum or Pennzoil Ultra. I've seen enough UOA's to come to that conclusion.
Mobil 1 uses PAO/Visom (Group III+) and V base oils.
Also, look at the MRV numbers for their 0w30 and 0w20. You wont' find a better cold weather oil than both of those.
Amsoil relies on bench tests which are often not that good at demonstrating oil superiorority. Amsoil is very good oil, but not better than Mobil 1, Pennzoil Platinum or Pennzoil Ultra. I've seen enough UOA's to come to that conclusion.
Mobil 1 uses PAO/Visom (Group III+) and V base oils.
Also, look at the MRV numbers for their 0w30 and 0w20. You wont' find a better cold weather oil than both of those.