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Synthetic motor oil is often recommended as a better alternative for car engines although it is pricier than regular motor oil. Consumer Reports recommends using a synthetic if you tend to make many small trips, use your car for intensive jobs such as towing, or live in very hot or cold conditions. Knowing which synthetic oil is the best for your vehicle requires some research.
1. Castrol EDGE Extended Performance
Car mechanic advice website Gear4Wheels gave Castrol EDGE Extended Performance a five star rating, stating it gives "the best possible protection for your motor." They back this up by citing Castrol's 15,000 mile guarantee. Castrol notes that this motor oil has been independently tested and found to be highly resistant to viscosity breakdown when compared to other commercially available synthetic oils.
Find it at major retail and auto supply stores for approximately $30 for a 5-quart bottle.
2. AMSOIL Signature Series Synthetic Oil
This oil gets high praise as "one of the best, if not the best synthetic oil" on the market. The downside of AMSOIL is it's not available online via large retailers; you need to purchase it either via the AMSOIL website or through an auto supply dealer.
Buyers on AMSOIL's site overwhelming recommend this product. The oil is backed by the company's confident guarantee of up to 25,000 miles, 700 hours of usage or one year between oil changes.
One quart is approximately $13 and a gallon is about $50.
3. Mobil 1 Synthetic Motor Oil
The highest rated synthetic motor oil on the Best Synthetic Oil Guide website, Mobil 1 handles high heat and icy cold temperatures with ease. It is the oil of choice for over half of NASCAR teams because of its excellent performance meeting the high mechanical demands of race cars.
It can be more expensive than other competing synthetic oils, however. A 5-quart jug runs about $35 to $45, depending on the store and specific blend.
4. Royal Purple HPS
Automotive how-to site MyCarNeedsThis gives Royal Purple HPS 5W-20 Synthetic Motor Oil with Synerlec Additive Technology its top rating with five out of five stars. The oil also gets very impressive ratings on Amazon.
Like other quality synthetic oils on this list, Royal Purple tends to be on the more expensive side. Royal Purple touts their proprietary Synerlec additive technology, claiming their special blend leads to their oil's superior performance compared to competitors.
Quarts go for about $10 each.
5. Valvoline MaxLife
Valvoline MaxLife SAE 5W-30 is an excellent choice if you want the benefits of a good synethetic oil without a hefty price tag. It's also recommended for colder weather climates, cars that have 75,000 or more miles, and for cars used for towing, hauling and other high performance work.
Reviewers on Pep Boys rate Valvoline MaxLife highly for value and dependability. The company states, "If you want to keep your car for life, this is the best motor oil for you."
Pricing gets as low as $7 for a one-quart bottle, depending on the retailer.
6. Shell Rotella T6 Full Synthetic Heavy Duty Engine Oil
If you have a diesel engine, Shell Rotella is a top synthetic oil pick. It's also recommended for use with motorcycles. Shell Rotella highlights their "triple protection" blend and the oil's fuel economy benefits. User reviews on the Shell Rotella website give the product a near perfect overall rating.
A one-gallon jug is priced at about $25.