Ever wonder if 0W20 is better than 5W20 synthetic engine oil?

It’s not really a question of whether 0W20 is better than 5W20 synthetic engine oil, the main reason 5W-20 or 0W-20 engine oil is specified for your engine is to improve fuel consumption and thereby meet regulations such as the CAFE (Corporate Average Fuel Economy) or EURO emissions.

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 passenger cars, 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.

Why is 0W20 better than 5W20 synthetic engine oil for emissions.

The change to a 5W-20 oil from the traditional 15W40 reduces manufacturers such as Honda and Ford's overall CAFE by a relatively small amount; typically in the tenths of a mile per gallon range. This is because 5W-20 engine oil is thinner than a 15W-40 motor 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.

Similarly OEM’s find 0W20 better than 5W20 synthetic engine oil in improving emissions.

The relative thining of the engine lubricant means that 0W20 is better than 5W20 synthetic engine oil – albeit by an almost immeasurable amount.

The problem, however, is that these ultra thin oils tend to be available as relatively expensive synthetic oils. Drivers of older vehicles find the cost prohibitive, and even drivers of vehicles where these oils are prescribed baulk at the cost.

Whilst motorists are aware that 0W20 is better than 5W20 synthetic engine oil for emissions they are concerned about the affect on the warranty if they use thicker oils.

This is not really the major concern: 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 oil, 5W-30, 10W-30, 0W-30, 10W-40 or 20W-50 or even a synthetic vs. a petroleum based oil will not affect warranty coverage. The manufacturer is required by 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, in North America 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.

While many argue whether 0W20 is better than 5W20 synthetic engine oil, what is of more importance is that a high quality oil, such synthetic motor oil produced by Habot Oil, is used.