The world powertrain community lost a vigorous and learned voice in January when Donald L. Miles, until recently General Motors Corp.'s chief engineer for V-6 engines, died at age 53.

Miles, who joined GM in 1970, was a tireless proponent of overhead-valve engine designs and became chief engineer for GM's 90-degree V-6 engines in 1988; in 1993, he also assumed responsibility for GM's 60-degree V-6 engines and later became well-known to the media as the brains behind the well-regarded and highly efficient 3800 Series II V-6 engine family. Although working with a dated design, Miles and his engineering teams updated the 3800 Series II to achieve ultra-low emissions and outstanding fuel economy.

In March 2001, Miles was appointed engineering director-vehicle accommodations and headed GM's mobility program.