WASHINGTON, D.C. — The U.S. Environmental Protection Agency (EPA) is looking into the pre-buy phenomenon rippling through truck order boards.

Although the EPA’s investigation is still in an early phase, there is some question as to whether seven major truck-engine manufacturers have improperly encouraged customers to buy engines before October, when clean-air regulations — widely expected to degrade engine performance — are scheduled to take effect.

The diesel manufacturers, including industry leaders Caterpillar and Cummins are prohibited from encouraging pre-buying under terms of a 1998 consent decree.

According to officials at both companies, neither has encouraged any pre-buying of its engines.

Ironically the EPA may in fact may be doing the encouraging. Based on data the agency released in January, the new engines are expected to cost about US$4,000 or $5,000 more than the standard $14,000 a truck engine currently goes for.

Fuel mileage, a matter of great concern for fleet operators, is expected to decline by about a significant 2.5 per cent. In addition, the EPA data suggests the new engines will require more-frequent maintenance.

Overall, the EPA technical paper estimates the total the life-cycle costs on the new engines at an additional $14,600 over and above current costs.

The consent decree, which created this situation, dates back to 1998. Under the Clinton administration, the EPA moved against Cat, Cummins and five other diesel makers. It claimed companies had circumvented clean-air rules by employing “defeat devices.” Engines were able to meet standards in lab tests, while belching out massive amounts of pollution on-highway the EPA argued.

While denying any wrongdoing, the makers settled those allegations by agreeing, among other things, to ensure that their truck engines would satisfy clean-air standards set for 2004 by this October.

As part of the investigation, a letter sent out by the EPA asks each of the companies that signed the decree if they have taken any action to encourage pre-buying, and requests extensive documentation in the form of copies of written communication with customers and similar information.