There is additional evidence there may be a big pre-buy going on, with truckers replacing their tractors before the more expensive ’07s come out.

According to truckinginfo.com, the sales of Class 8 trucks were up nearly 20 percent in April of this year compared to April 2005. And that’s in spite of the fact that overall trucks sales – including classes 1 through 3 – were down about 2percent.