The question that is now being ask more and more by fleet mangers and owners is what is the best synthetic oil for diesel engines?
There is a shift in progress of viewing how synthetic diesel oil can be bring fuel efficiency and cost effectiveness to trucking companies.The every increasing costs of fuel has now brought about the search to cut cost on consumption.

FleetOwner.com says:
A soon-to-be released study by global research firm Frost & Sullivan predicts major change for the U.S. engine oil market for Class 4-8 trucks by 2018, driven heavily by the need to boost fuel efficiency ahead of new federal greenhouse gas (GHG) mandates for commercial trucks along with increased use of smaller engine blocks and hybrid propulsion systems.
Can synthetic oil actully bring savings over the cost of it? I mean thats what most always say its good but cost too much.
Synthetic diesel oil will boost the fuel economy, plus it will help reduce oil consumption and it alos has lower volatility (evaporation) than conventional motor oils. Because less oil vapor passes into the combustion chamber, oil consumption and emissions are reduced. Lower volatility means that the synthetic diesel oil retains its viscosity after high-temperature service for excellent fuel economy not to mention the protection that conventional oil cannot match.

Again what FleetOwner stated:
“Right now, one of the issues with low viscosity oils is that they do not apply well in warmer regions of North America,” Lau pointed out. “Yet [diesel] fuel costs across all of the U.S. and Canada are predicted to only keep rising, so fleets want the fuel saving advantage of a low viscosity fluid. Our fleet focused research indicates steadily rising interest in advanced engine oils which is already translating to rising aftermarket demand for synthetics and semi-synthetics. It is only a matter of time before we see these fluids in the factory-fill market.”

Well not all synthetics are so.The best synthetic oil for diesel engines is really down to one statement the proof is in the pudding.

600 K Mack Trucks ??? You bet this is worth the few minutes to watch

Wow thats some proof!