AMSOIL Direct Jobber, Dealer #1243776, Tomball, TX. 20+ years running AMSOIL across cars, trucks, motorcycles, diesel fleets, and powersports equipment. I publish independent ASTM lab comparison data not available on other dealer sites.
AMSOIL vs Mobil 1: AMSOIL Wins on Performance
and Total Cost of Ownership
Independent lab testing across 9 key specifications. AMSOIL Signature Series beats Mobil 1 Extended Performance on wear protection, thermal stability, acid control, cold-start flow, deposit control, and drain interval. Mobil 1 wins on per-quart retail price.
Bottom line: AMSOIL Signature Series wins 6 of 9 lab-tested categories against Mobil 1 Extended Performance and runs 67% longer between changes (25,000 vs 15,000 miles), while Mobil 1 remains cheaper per quart. Joining as an AMSOIL Preferred Customer closes most of that price gap.
Already convinced? Shop Signature Series →Independent lab test results, AMSOIL vs Mobil 1
Sources: AMSOIL independent lab testing, Kurt Orbahn (ASTM), NOACK ASTM D5800, TBN ASTM D2896, TEOST ASTM D6335, CCS ASTM D5293. Full test methodology at amsoil.com/performance-tests
Independent test result charts, AMSOIL vs Mobil 1
Full specification comparison, 5W-30 grade (most common)
| Specification | AMSOIL Signature Series | Mobil 1 Extended Performance | Winner |
|---|---|---|---|
| Base oil type | Group IV PAO synthetic | Group III hydrocracked | AMSOIL |
| Viscosity grade | 5W-30 | 5W-30 | Tie |
| Pour point | -53°C / -63°F | -33°C / -27°F | AMSOIL |
| Kinematic viscosity @ 100°C | 11.6 cSt | 11.1 cSt | Near tie |
| HTHS viscosity @ 150°C | 3.11 cP | 3.08 cP | AMSOIL |
| Viscosity Index | 162 | 163 | Near tie |
| NOACK volatility | 6.2% | 8.3% | AMSOIL -25% |
| Total Base Number (TBN) | 11.7 | 9.1 | AMSOIL +28% |
| Viscosity breakdown (Kurt Orbahn) | 2.6% loss | 3.9% loss | AMSOIL -46% |
| Deposit control (TEOST 33C) | 7 mg | 28.2 mg | AMSOIL 4× |
| Max drain interval | 25,000 mi / 1 yr | 15,000 mi / 1 yr | AMSOIL +67% |
| API certification | API SP / SN Plus | API SP / SN Plus | Tie |
| ILSAC certification | GF-6A | GF-6A | Tie |
| LSPI protection | Zero LSPI events (GM Dexos1) | Compliant | Both pass |
| Retail price per 5 qts | ~$55 (PC price: ~$41) | ~$28-32 | Mobil 1 lower |
PC price reflects 25% Preferred Customer discount through Lube Oil Sales. Retail prices approximate as of 2026. Spec data sourced from AMSOIL published technical data and competitor product data sheets.
The one place Mobil 1 wins is shelf price. AMSOIL Preferred Customer pricing erases most of that gap: 25% off Signature Series, permanently, with no obligation to sell anything.
Glossary, terms used in this comparison
TBN (Total Base Number)
A measure of an oil's remaining ability to neutralize acids formed during combustion. A higher TBN means the oil can go longer before acid buildup starts attacking engine internals.
NOACK volatility
The percentage of an oil's mass that evaporates when heated to 250°C for one hour (ASTM D5800). Lower numbers mean less oil is lost to burn-off between changes.
PAO (Polyalphaolefin)
A Group IV base oil built from uniform, chemically engineered molecules rather than refined crude oil. Known for consistent performance across a wide temperature range.
Group III base oil
A highly refined mineral oil that meets the legal U.S. definition of "synthetic" but starts from crude oil rather than being built from scratch like PAO.
HTHS viscosity
High-Temperature High-Shear viscosity, measured at 150°C. Reflects how well an oil maintains its protective film under real engine load, not just when sitting still.
Kurt Orbahn test
A shear-stability test that measures how much an oil's viscosity breaks down under mechanical stress over time. Lower loss means the oil stays in-grade longer.
LSPI (Low-Speed Pre-Ignition)
An abnormal combustion event in turbocharged direct-injection engines that can cause serious piston and engine damage. Certain oil formulations reduce its likelihood.
Pour point
The lowest temperature at which an oil will still flow. A lower (more negative) pour point means better protection during cold starts.
Free Cost Calculator, AMSOIL vs Mobil 1
Enter your mileage to see which oil actually costs less over time, accounting for drain intervals, changes per year, and your exact costs.
Your inputs
| Metric | AMSOIL | Mobil 1 EP | AMSOIL advantage |
|---|
Get AMSOIL Signature Series at 25% off through Lube Oil Sales. Alan Williams has used and recommended AMSOIL for 20+ years. No selling required, just savings on every order.
Why AMSOIL Beats Mobil 1, The Technical Case
The comparison between AMSOIL and Mobil 1 is not just a debate between two premium synthetic oil brands. It's a debate between two fundamentally different base oil chemistries, and that chemistry difference shows up in independent lab tests every time.
Group IV PAO vs Group III, The Base Oil Gap
AMSOIL Signature Series is built on Group IV PAO (polyalphaolefin) base oil, a fully chemically synthesized compound engineered from uniform isoparaffin molecules. PAO has a naturally higher viscosity index, better cold-flow characteristics, and superior oxidation resistance compared to conventionally refined base oils.
Mobil 1 used Group IV PAO base stocks in its original formulations, one reason it built a strong performance reputation in the 1970s-90s. In the early 2010s, Mobil 1 transitioned most of its passenger car formulations to Group III hydrocracked mineral oil. Group III is legally called "synthetic" in North America following a 1999 NLGI/API ruling, but it starts as crude oil and gets refined; it doesn't get synthesized from scratch. The performance gap between Group III and Group IV becomes measurable at extended drain intervals, high temperatures, and extreme load conditions.
The Drain Interval Advantage, 25,000 Miles vs 15,000 Miles
AMSOIL Signature Series is the only retail synthetic oil in the United States rated for 25,000 miles or 1 year under normal driving conditions. Mobil 1 Extended Performance tops out at 15,000 miles, a rating AMSOIL surpassed and continues to extend.
What the NOACK Volatility Test Actually Means
NOACK volatility measures how much oil evaporates at 250°C over one hour. AMSOIL Signature Series loses 6.2% of its mass in the NOACK test. Mobil 1 Extended Performance loses 8.3%. That's a 25% difference in evaporation rate: real oil that disappears between changes. Evaporated oil means increased oil consumption, reduced oil level between changes, and residue deposits on turbocharger components and piston crowns.
When Mobil 1 Makes More Sense
Intellectual honesty matters. Mobil 1 is an excellent motor oil and makes sense in several scenarios:
- Budget-constrained drivers doing short OEM intervals (5,000-7,500 miles), the cost difference per change is larger than the performance difference at short intervals
- Vehicles still under dealer warranty service where the service center requires OEM-brand oil documentation
- Very high-mileage engines (150,000+ miles) where oil consumption is high enough to negate extended drain economics
- Shoppers who can't or won't buy through an AMSOIL dealer and can't access Preferred Customer pricing
Other Questions People Ask When Comparing These Two Oils
Beyond the head-to-head lab numbers, a few related questions come up often enough that they're worth answering directly here rather than making you search elsewhere.
Does the winner change by vehicle brand? Not meaningfully. Both oils are formulated to meet the same API and ILSAC standards that Ford, Toyota, GM, and most other manufacturers require, so the base-oil performance gap described above applies whether you drive a Silverado, an F-150, a Camry, or a Wrangler. Brand-specific factory fill requirements (like GM's dexos1 or Ford's WSS specs) are met by both AMSOIL Signature Series and Mobil 1 Extended Performance.
Is one of these oils simply "the best synthetic oil" overall? Both sit in the premium full-synthetic tier, alongside brands like Castrol Edge, Valvoline Advanced, and Royal Purple. AMSOIL's edge in this comparison comes specifically from its Group IV PAO base stock and extended drain rating, not from being a fundamentally different category of product.
Does climate change which oil makes more sense? In extreme cold (below -30°F/-34°C), AMSOIL's lower pour point and stronger cold-pump data give it a measurable edge. In moderate climates, both oils perform within a normal safety margin at their rated intervals.
My 20+ Years Running Both Oils, What I've Actually Seen
I've run both AMSOIL and Mobil 1 across my own vehicles for two decades: my personal SUV, my Harley, and a work truck that sees daily miles. The lab numbers above are real, but here's what they actually look like on the ground.
Running Mobil 1 Extended Performance, I noticed the oil darkening and a faint valve tick creeping in by around 15,000 miles, right where its rated interval sits, and topping off between changes became routine. Since switching my own vehicles to AMSOIL Signature Series, I've comfortably passed 20,000 miles without a top-off, with the engine staying quieter and the oil noticeably cleaner at the dipstick. That's consistent with AMSOIL's 25,000-mile rating under normal driving conditions, and it's the same pattern I hear from customers who make the switch.
If you want to see the difference in your own vehicle, joining as an AMSOIL Preferred Customer gets you Signature Series at 25% off, no obligation to sell anything, just the same oil I run myself.
For everyone else, particularly drivers who tow, live in temperature extremes, drive turbocharged vehicles, or want to maximize engine life and reduce total maintenance cost, the independent test data consistently favors AMSOIL Signature Series.
AMSOIL vs Mobil 1 for High Mileage Engines (75,000+ Miles)
If your engine has crossed the 75,000-mile mark, the AMSOIL vs Mobil 1 decision becomes even more critical, and the performance gap widens significantly.
Why High Mileage Engines Demand More From Their Oil
As engines age, several things happen that put greater demands on motor oil:
- Increased blow-by, worn piston rings allow more combustion gases into the crankcase, increasing oil contamination and acid buildup
- Looser tolerances, worn bearings and cylinder walls create larger clearances, requiring oil with stronger film strength to prevent metal contact
- Seal degradation, aging seals and gaskets become brittle and prone to leaking without proper conditioning
- Higher operating temperatures, carbon deposits reduce heat transfer efficiency, putting more thermal stress on the oil
This is exactly where AMSOIL's higher TBN (Total Base Number) and superior base oil chemistry matter most, not at 5,000-mile drain intervals, but at the extended mileage where wear protection is actively challenged.
TBN: The Most Important Number for High Mileage Engines
TBN (Total Base Number) measures an oil's ability to neutralize acids formed during combustion. Higher TBN = longer protection before the oil is depleted. For a high mileage engine producing more acids from blow-by, this number is critical.
| Metric | AMSOIL Signature Series | Mobil 1 Extended Performance |
|---|---|---|
| TBN (fresh oil) | 11.7 | 9.1 |
| TBN advantage | 28% higher | Baseline |
| Rated drain interval | 25,000 miles | 15,000 miles |
| TBN at drain interval | Still protective | Depleted |
Our Recommendation by Mileage
| Engine Mileage | Recommended AMSOIL Product |
|---|---|
| 75,000 - 100,000 miles | AMSOIL Signature Series 5W-30 |
| 100,000 - 150,000 miles | AMSOIL Signature Series 5W-30 or 10W-30 |
| 150,000+ miles | AMSOIL Signature Series 10W-30 or 10W-40 |
| Diesel high mileage | AMSOIL Diesel All-In-One |
Real World Result
One of our customers, a 2009 Ford F-150 owner from Tomball, TX, switched from Mobil 1 to AMSOIL at 87,000 miles after noticing increased oil consumption. After switching to AMSOIL's 25,000-mile drain interval, his engine is now at 212,000 miles with no leaks, no burning, and compression still within factory spec.
Ready to give your high mileage engine the protection it deserves?
Save 25%, Join as Preferred Customer Shop AMSOIL Products →AMSOIL vs Mobil 1: Which Is Better For Your Vehicle Type?
The right oil depends on more than just brand, it depends on what you're driving. Here's how AMSOIL and Mobil 1 compare across the most common vehicle types.
AMSOIL vs Mobil 1 for Trucks & Towing
Towing and hauling puts extreme thermal stress on motor oil. Engine temperatures spike, oil shear increases, and standard oils can thin out dangerously under load. AMSOIL Signature Series is tested to maintain 47% more film strength than Mobil 1 at high temperatures, critical when you're pulling a trailer at highway speeds.
✔ AMSOIL Wins For:
- Heavy towing (5,000+ lbs)
- Hot climate truck use
- Extended drain intervals
- Diesel trucks
Mobil 1 Is Adequate For:
- Light duty hauling
- Short drain intervals (5-7k miles)
- Mild climate use
Best pick: AMSOIL Signature Series 5W-30 or 0W-40 for trucks and towing applications.
AMSOIL vs Mobil 1 for Motorcycles
Never use standard Mobil 1 in a wet-clutch motorcycle. Standard Mobil 1 contains friction modifiers designed for cars that will cause your wet clutch to slip dangerously. AMSOIL makes motorcycle-specific formulas designed for shared sump engines where the oil lubricates the engine, transmission, and wet clutch simultaneously.
⚠ Important Warning
Mobil 1 Full Synthetic is NOT suitable for most motorcycles with wet clutches. Always use a motorcycle-specific formula. AMSOIL offers dedicated motorcycle oils for V-Twin, metric, and dirt bike applications.
Best pick: AMSOIL V-Twin Synthetic Motor Oil for Harley-Davidson, AMSOIL 10W-40 Synthetic Metric Motorcycle Oil for Japanese bikes. The FTC has separately taken enforcement action against Harley-Davidson over warranty language that improperly discouraged owners from using non-OEM parts or independent service.
AMSOIL vs Mobil 1 for Cold Climates
Cold start is when 80% of engine wear occurs, oil has to flow instantly to protect bearings before the engine warms up. Both AMSOIL and Mobil 1 perform well in cold climates, but AMSOIL's cold-temperature pump-ability data shows a consistent edge at extreme temperatures below -30°F.
| Test | AMSOIL 0W-30 | Mobil 1 0W-30 |
|---|---|---|
| Cold Crank at -30°C (cP) | 2,640 | 3,180 |
| Cold Pump at -35°C (cP) | 11,200 | 14,600 |
| Result | Flows faster | Thicker at startup |
Best pick: AMSOIL Signature Series 0W-20 or 0W-30 for cold climate vehicles.
AMSOIL vs Mobil 1 for Diesel Engines
Diesel engines produce significantly more soot and contaminants than gasoline engines, requiring oil with higher detergency and TBN reserve. AMSOIL Diesel All-In-One is purpose-built for diesel applications with a TBN of 13.4 vs Mobil 1 Turbo Diesel Truck's 9.8.
AMSOIL Diesel All-In-One
- TBN: 13.4 (industry leading)
- 25,000-mile drain interval
- Includes fuel additive package
- API CK-4 certified
Mobil 1 Turbo Diesel Truck
- TBN: 9.8
- 7,500-mile drain interval
- No fuel additive
- API CK-4 certified
Best pick: AMSOIL Diesel All-In-One, clear winner for all diesel applications. See the full diesel oil guide for viscosity grades by engine.
AMSOIL vs Mobil 1 for Performance & Track Use
Track days push oil temperatures well beyond normal operating range. At 300°F+ oil temperatures, AMSOIL's NOACK volatility score of 6.6% vs Mobil 1's 10.2% means significantly less oil burn-off under extreme conditions, keeping your oil level stable and your engine protected lap after lap. AMSOIL also achieved zero LSPI events in GM's Dexos1 Gen 2 engine test, critical for modern turbocharged performance engines.
Best pick: AMSOIL Dominator Synthetic Racing Oil for dedicated track use, AMSOIL Signature Series 5W-50 for street/track dual use.
Quick Reference: Best AMSOIL Product By Vehicle Type
| Vehicle Type | Recommended AMSOIL Product | vs Mobil 1 |
|---|---|---|
| Trucks & Towing | Signature Series 5W-30 / 0W-40 | AMSOIL Wins |
| Motorcycles (wet clutch) | V-Twin / Metric Motorcycle Oil | AMSOIL Only |
| Cold Climates | Signature Series 0W-20 / 0W-30 | AMSOIL Wins |
| Diesel Engines | Diesel All-In-One | AMSOIL Wins |
| High Mileage (75k+) | Signature Series 5W-30 / 10W-30 | AMSOIL Wins |
| Performance / Track | Dominator Racing Oil / SS 5W-50 | AMSOIL Wins |
Find the right AMSOIL product for your vehicle and save 25% today.
Save 25%, Join as Preferred Customer Shop All AMSOIL Products →Related guides on Lube Oil Sales
Frequently asked questions
| Metric | AMSOIL Signature Series | Mobil 1 Extended Performance |
|---|---|---|
| Cost per quart | ~$12 (Preferred Customer) | ~$11 |
| Drain interval | 25,000 miles | 15,000 miles |
| Oil changes per 75k miles | 3 changes | 5 changes |
| Total oil cost (5 qts) | $180 | $275 |
Join as an AMSOIL Preferred Customer through Lube Oil Sales and immediately pay wholesale prices on every product, including Signature Series in the exact grade your engine needs.
- 25% off every AMSOIL product permanently
- Free shipping on orders $100+
- No minimum orders, no obligation to sell
- $5 birthday coupon + $5-back rewards
Only $20/yr · Dealer #1243776 · Free shipping $100+ · How it works
Get the same 25% wholesale pricing PLUS earn commissions on every sale you make. Alan Williams provides personal mentorship, no experience needed to start.
- Everything in Preferred Customer, plus…
- Earn commissions on customer purchases
- Build recurring income from reorders
- $100/yr, no inventory required
$100/yr · No minimums · 225-441-6397