The big news last week that Caterpillar plans to exit the on-highway diesel engine market as of 2010 probably didn't come as a complete surprise to anyone in the trucking industry. Over the past several months, as other diesel engine manufacturers were loudly proclaiming their plans to meet the Environmental Protection Agency's 2010 emissions standards, Cat had been notably quiet. In fact, so little news has come out of Peoria in the past year that I had started to wonder if the company had shut down its public relations department. In last week's press release from the company, Cat's Group President, Douglas R. Oberhelman, said, "Caterpillar and our dealers will continue to provide product support and service beyond 2010 for all Caterpillar on-highway engines regardless of truck brand." That will, no doubt, be a relief to the countless fleets that depend on Cat power, but if I were in charge of purchasing for a fleet and I had 2008s or 2009s on order with Cat engines, I think I might feel a little betrayed and abandoned. This isn't the last we'll see of Caterpillar, of course--the company also announced a strategic alliance with International Trucks, and plans to introduce its own line of severe-service trucks at the same time they leave the on-highway market. Just the same, Cat's move will leave a big hole--and probably some hard feelings--in the industry.