New for model year 2001 and Newer: Ford and Honda specify 5W-20 motor oil for most all cars and light trucks.

Here are the facts behind 5W-20:

Question: My owners manual species 5W-20 oil. Do I really need to use 5W-20 oil and why did my 2000 model year vehicle require a 5W-30 oil, while the exact same engine in my 2001, 2002 and newer engines "requires" a 5W-20 oil?

Answer: You do not need to use a 5W-20 oil. Do not let your dealer scare you by telling you that you have to use it for your warranty. That is a tactic that some dealerships use to scare customers. Once you know the facts and the Federal Magnusson Moss Act law you will be much better informed to protect your rights and use the type of oil you want to use.

The main reason 5W-20 was specified for your engine is to increase the CAFE (Corporate Average Fuel Economy) reported to the Federal Government. CAFE is the combined average fuel economy of all of a vehicle manufacturers product line. Minimum CAFE levels are specified by the Federal Government. In order for a vehicle manufacturer to continue selling profitable large trucks and SUV's, which typically have poor fuel mileage ratings, as compared to smaller cars, and still meet mandated CAFE requirements, they must also sell enough of the smaller cars which have much better fuel economy ratings to offset the poor fuel economy ratings of the larger vehicles. For model year 2001, the change to a 5W-20 oil will allow Ford and Honda's overall CAFE to increase by a very small amount, typically in the tenths of a mile per gallon range. 5W-20 oil is a lighter viscosity than a 5W-30 oil and therefore has less internal engine frictional losses, or less drag on the crankshaft, pistons and valvetrain, which in turn promotes increased fuel economy. This increased fuel economy is virtually undetectable to the average motorist without the use of specialized engine monitoring and testing equipment under strictly controlled test track driving when compared to a 5W-30, 10W-30 or a 0W-30 viscosity motor oil.

Question: Could using a 5W-30, 10W-30, 0W-30 or even a 10W-40 or 20W-50, oil in my vehicle which specifies a 5W-20 oil void my new car warranty?

Answer: Absolutely not. Vehicle manufacturers only recommend using motor oils meeting certain viscosity grades and American Petroleum Institute service requirements. Whether a motor oil is a 5W-20, 5W-30, 10W-30, 0W-30, 10W-40 or 20W-50 (for racing and high performance applications in, for example, a Cobra R Mustang) or even a synthetic vs. a petroleum based oil will not affect warranty coverage. The manufacturer is required by Federal Law to cover all equipment failures it would normally cover as long as the oil meets API service requirements and specifications and was not the cause of failure. In addition, the Federally mandated Magnuson - Moss Act states that a manufacturer may not require a specific brand or type of aftermarket product unless it is provided free of charge. If your dealership continues to tell you that you must use 5W-20 motor oil and or/ a specific brand of 5W-20 motor oil, then ask them to put it in writing. Their position is inaccurate, and, in fact violates existing law.*

Additionally, if there is ever a question of whether or not a particular motor oil was the cause of an engine failure make sure to get a sample of the used oil in a clean bottle, typically 6 oz. minimum. The oil can then be sent to two independent testing labs for analysis. This is standard procedure for most commercial vehicles, trucking, construction/excavation and fleet companies and there are numerous certified test labs all over the country. Remember, a knowledgeable and informed consumer is your best defense against being taken advantage of by a car dealership service center.

Note: If a car or truck dealership, service center or other business states that using AMSOIL motor oil in your vehicle will void your new car warranty, ask for that statement in writing and send it to AMSOIL technical Services. If the business won't provide the statement in writing send AMSOIL Technical Services a letter identifying who made the statement, the name and location of the business and what the statement was. AMSOIL will then send a letter to the business informing them that their position is inaccurate, and, in fact, violates existing law. Your name will be held in confidence.

AMSOIL mailing address: AMSOIL Inc., AMSOIL Bldg., Superior, WI 54880

For those consumers that still must use a 5W-20 oil, even after reading this informative article, AMSOIL does manufacture a 5W-20 synthetic motor oil, called XL-7500 5W-20. It is a 7500 mile/6-month motor oil. AMSOIL's 5W-20 synthetic motor oil provides outstanding wear protection and increased power, performance and fuel economy in high and low temperatures and also meets and exceeds the Ford and Honda specifications.

For even better performance and protection we recommend using AMSOIL's Series 2000 0W-30 synthetic motor oil. This is the top performing AMSOIL Motor Oil for gasoline powered light trucks and passenger cars. It uses race-proven technology and provides unsurpassed fuel efficiency and better wear protection than other conventional and synthetic motor oils. It is a 35,000 mile/1-year change interval motor oil. Use it in conjunction with AMSOIL's Absolute Efficiency Oil Filter's that specify a change interval of 25,000 miles/12 months, whichever comes first.