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Honest John Ask Honest John » As a petrochemist I concur with your comments on the effects of driving habits on DPFs and EGR valves.

As a petrochemist I concur with your comments on the effects of driving habits on DPFs and EGR valves.

As a petrochemist specialising in engine lubrication I have to agree with your comments entirely. It's not commonly known that driving habits have an effect on vehicle reliability, and short journey "shopping car scenarios" will contribute to EGR issues. The other not so well-known problem is on Diesel Particulate Filters which become blocked because the exhaust system never gets hot enough to go into a regenerative cycle, where carbon deposits are normally burned away to clean the DPF.

Equally important is the quality of engine oil that's used. Ford cars have gone through a succession of engine oil specifications from fuel-efficient 5w30 (Ford M2C 913B, then Ford M2C 913C and Ford M2C 913D) viscosity grades to more recently a more fuel-efficient 5w20 (Ford M2C 948B). The wrong choice when topping up a car can and does have long-term issues, not just to reliability, but also fuel economy as well.

Asked on 27 July 2013 by MM, Technical Director, Millers Oils

Answered by Honest John
Many thanks. I've been banging on about the DPF issue for several years and have probably turned thousands of potential victims from making an inappropriate choice. But I was not aware of Ford's switch from 5w30 to 5w20.
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