I often wonder how frequently this column strikes a chord with readers. Sure, I've routinely received emails and phone calls. But never have I received as much feedback as I did in response to my December “Bold Moves” column, in which I supported ATA's rulemaking petition to require tamper-proof speed limiting devices on all trucks weighing more than 26,000 lb.

In general, reader responses fit into one of two categories: general distaste for any provision that limits top speed or concern over my statement regarding the correlation between fuel savings and reduced vehicle speed.

Regarding the latter, I readily admit that I incorrectly cited a Maintenance Council study, noting: “…a 1996 Maintenance Council report estimated a one-mile-per-gallon savings for each 0.1 mile reduction in truck speed.” That statement was in error. The correct citation is: “…a 1996 Maintenance Council report estimated a one-mile-per-gallon-savings for a 10 mph reduction in speed from 65 mph to 55 mph.

Again, I apologize for this blunder. That being said, the fuel savings benefit of reduced truck speed is well documented. For example, in a study entitled “Factors Affecting Fuel Economy, Goodyear Tire and Rubber Co. notes that for the typical tractor and van trailer, total horsepower requirement at 65 mph is 40% greater than at 55 mph. Goodyear's analysis found an 8% decrease in mpg for every 5 mph increase in speed over 55 mph.

Readers with a distaste for speed limiting devices generally felt that the possible increase in truck crashes caused by the “differential speed” between cars and trucks would offset any safety benefits of reduced truck speed limits.

On this point, I stick to facts noted in my December column. The relationship between speed and crashes has been proven time and again. Granted, we need to consider the entire body of research (including data on the unintended consequences of a truck/car speed differential) during a formal rulemaking process.

Speaking of truck speed, the subject is addressed in the FMCSA's Notice of Proposed Rulemaking, “Electronic On-Board Recorders (EOBR) for Hours of Service Compliance,” which was announced last month. (See Lead News, p. 8). The intent of the proposal is to improve highway safety by fostering the development of new EOBR technology for HOS compliance, encourage its use through incentives, and require its use by operators with serious and continuing HOS compliance problems.

The proposal outlines specifications for new EOBRs, including the requirement that such devices accurately record a vehicle's physical location at intervals no greater than once per-minute. In addition, the proposal would require the devices to accurately record distance traveled, with an error rate no greater than 1% of the distance traveled within a 24-hour period.

It is noteworthy that the proposal indicates that speed monitoring is “outside the scope” of the rulemaking. That being said, my hunch is that observers will note that speed determination is possible, given that the devices will record accurate measures of time, location and distance traveled. More on that in a future column.

Realizing the sensitivity of “legislated” truck speed requirements, I support ATA's petition and urge FMCSA to take a leadership position by convening a rulemaking proposal that provides a full and unbiased vetting of the safety implications of reduced truck speed. The motoring public deserves nothing less.


Jim York is the manager of Zurich Service Corp.'s Risk Engineering Transportation Team, based in Schaumburg, IL.