Both the Fuel Economy and Edge are synthetically made for all types of gasoline engines including those with high performance, multi-valve, fuel-injectors, supercharge, and turbocharge.
Fuel economy as the name indicates is dedicated to improving the fuel economy, therefore, its fully advanced formula provides low friction along with high thermal stability.
This results in the high oxidation stability of this oil, aiding its fuel economy. Its performance is remarkable in cold weather due to its highly optimized molecular structure. It has active cleaning agents such as detergents, dispersants, and anti-foam agents which prevent the build-up of sludge.
It also has a decent amount of anti-wear additives to relieve friction inside the engine, providing wear protection.
On the other side, Edge is formulated with “Fluid Titanium Technology” which is concentrated on improving the motor oil strength, hence, allowing the maximum performance of the engine. Therefore, the expertise of this oil lies in working under high pressure by effectively reducing metal to metal contact.
It is sturdy enough to maintain its same extreme performance for the whole oil change interval. It has a decent quantity of additives to prevent deposits formations inside the engine. It also somewhat improves the fuel economy by providing respectable performance in high temperatures.
Table of Contents
Quick Comparison
| Characteristics | Mobil 1 Advanced Fuel Economy (0W-20) | Castrol Edge (0W-20) |
| Nature of oil | Full Synthetic | Full Synthetic |
| Compatible with engines | Gasoline only | Gasoline only |
| Viscosity grades | 0W-16, 0W-20, 0W-30 | 0W-16, 0W-20, 5W-20, 5W-30, 5W-50, 10W-30, 10W-40 |
| ILSAC | GF-5 | GF-5 |
| API | SN, SM, SL | SN Plus |
| ACEA | Unavailable | A1/B1 |
| Oil Change Frequency (miles) | 10,000 | 5000 |
| Price (5 Quart Bottle) | 27.46$ | 24.47$ |
Wear Resistance
The basic function of the anti-wear additives is to avoid the friction caused by metal-to-metal impact and reduce wear. They do this by clinging to the metal surface and forming an oil surface, acting as a boundary between metal parts. A higher concentration of these ensures a highly resistant oil film around metal parts.
Fuel Economy is outclassed by its competitor in the competition of wear prevention. It contains only a higher concentration of molybdenum whereas all the other anti-wear additives are present in higher quantities in Edge. It also contains a special titanium anti-wear additive, boosting its wear reduction capabilities to the next level.
| Motor Oils (0W-20) | Phosphorus Concentration (ppm) | Zinc Concentration (ppm) | Molybdenum Concentration (ppm) | Titanium Concentration (ppm) | Boron Concentration (ppm) |
| Mobil 1 Advanced Fuel Economy | 709 | 730 | 88 | <1 | 102 |
| Castrol Edge | 741 | 817 | 71 | 23 | 138 |
Viscosity Assessment
Viscosity is simply explained as resistance to flow whereas the kinematic viscosity of the oil is the same internal resistance of the oil to flow but without any external force acting upon it except for gravity. On the other hand, the viscosity index shows the effect of temperature on the kinematic viscosity of the oil.
When comparing density, it was tested higher in Fuel Economy, meaning its density will help it in achieving its better kinematic viscosity. At forty degrees Celsius Fuel Economy leads by a small margin and this victory is maintained by this oil at the hundred-degree Celsius mark as well. This also helps it to achieve a higher viscosity index since its kinematic viscosity was less affected by the temperature changes.
| Motor Oils (0W-20) | Density @15° C | Kinematic Viscosity at 40° C (cSt) | Kinematic Viscosity at 100° C (cSt) | Viscosity Index |
| Mobil 1 Advanced Fuel Economy | 0.85 | 45.97 | 8.80 | 174 |
| Castrol Edge | 0.841 | 43.6 | 8.4 | 172 |
Impact on Catalytic Converter Performance
The performance of the catalytic converter is affected by the number of incombustible materials inside the oil along with the concentration of anti-wear additives zinc and phosphorous. When the oil burns these additives turn into ash, blocking the catalytic converter. Thus, its performance is reduced.
Upon testing, it was found that both these oils only have a single percentage of their mass’s incombustible, therefore, in terms of incombustible material both are ranked equally. Nevertheless, the combined quantities of both zinc and phosphorus were found higher in Edge, hence, it will form a greater quantity of ash when burnt. This concludes that it will greatly hinder the performance of the catalytic converter.
| Motor Oils (0W-20) | Sulfated Ash Content (⸓) | The concentration of zinc and phosphorus (ppm) |
| Mobil 1 Advanced Fuel Economy | 1 | 1439 |
| Castrol Edge | 1 | 1558 |
Sludge clean-up ability
As the engine oil is used it gets contaminated and these contaminants join together to form sludge. Detergents present inside the oil prevent the build-up of sludge and keep the engine clean. They are very necessary since the massive build-up of sludge can clog the pathway of oil and cause a great amount of distress.
The fuel economy has a greater number of all detergents except for sodium but it is still very effective in countering the sludge problem. Whereas Edge gets left behind a little due to a comparatively lower concentration of detergents, making it less capable for cleaning sludge.
| Motor Oils (0W-20) | Calcium Concentration (ppm) | Magnesium Concentration (ppm) | Sodium Concentration (ppm) | Silicon Concentration (ppm) | Barium Concentration (ppm) |
| Mobil 1 Advanced Fuel Economy | 1120 | 789 | <5 | 6 | <1 |
| Castrol Edge | 953 | 741 | 11 | 4 | <1 |
Oil Consumption and Fuel Economy
The rate at which the oil evaporates is its volatility rate. A highly volatile oil will soon get enough vapors that could be ignited for an instant, such oil will have a lower flash point temperature and will be consumed rapidly. All these characteristics will decrease the fuel economy.
Here Edge vaporizes at a faster rate than its counterpart, causing it to achieve its flashpoint at a much lower temperature. This means that it will be consumed at a higher rate in comparison to Fuel Economy. As a result, the fuel economy of this oil will be much lower relatively.
| Motor Oils (0W-20) | Volatility rate (⸓) | Flash Point Temperature (°C) |
| Mobil 1 Advanced Fuel Economy | 10.7 | 226 |
| Castrol Edge | 12 | 206 |
Characteristics in Cold weather
In cold weather since the oil can’t easily flow naturally, hence, its dynamic viscosity is measured which is the resistance to flow when the oil is pushed by an external force. While pour point temperature is the limit below which oil will be unable to flow even with external force.
At negative thirty-five degrees, the dynamic viscosities of both these oils were measured and it was revealed that the Fuel Economy oil will flow better due to its lower dynamic viscosity. Similarly, it will freeze at a much lower temperature than its counterpart, granting it superiority in extremely cold conditions.
| Motor Oils (0W-20) | Dynamic Viscosity @ -35° C (mPas) | Pour point temperature (° C) |
| Mobil 1 Advanced Fuel Economy | 4182 | -51 |
| Castrol Edge | 5175 | -42 |
Total Base Number
The bases available inside the oil are necessary since they cancel out the acids formed during the combustion as by-products which can cause corrosion. If an oil has a greater amount of these base additives, it could be effective for a long time.
The higher base reserves are tested in Fuel Economy; hence, it was able to be used for a longer oil drain interval up to 10,000 miles. But the Edge was unable to compete in this regard as its base stocks are significantly lower than the other oil, causing it to be effective only for a limited period of 5000 miles which is half of the distance provided by its counterpart.
| Motor Oils (0W-20) | TBN (mg KOH/g) |
| Mobil 1 Advanced Fuel Economy | 9.53 |
| Castrol Edge | 7.61 |
Cost Analysis
Price of five-quart bottle of Fuel Economy is available for 27.46 US dollars while the same size bottle of Edge could be bought for 24.47 US dollars. This price difference is due to the better performance of Fuel Economy regarding catalytic converter performance, sludge reduction, volatility, kinematic viscosity, viscosity index, cold temperature performance, and a higher TBN. While Edge being lower priced is only better at wear-reducing. Therefore, we declare the Fuel Economy to be the cost-effective option out of both these oils.
Quick Summary
- These are synthetic oils only suitable for gasoline engines.
- Fuel economy is more catalytic friendly than its counterpart.
- The sludge cleaning ability of the Fuel Economy is higher.
- The volatility of the Fuel Economy is lower.
- Edge has better anti-wear additives for reducing friction and wear.
- The kinematic viscosity at medium and high temperature along with viscosity index is higher of Fuel Economy.
- Fuel economy freezes late and provides better performance in cold temperatures.
- TBN of Fuel Economy is higher.
- Fuel Economy is costlier yet cost-effective.
