Durallymax. Good point on the truck experience in those 3 years 07, 08, 09. One thing on that......used truck buyers, myself included, either avoid those years or have the DPF removed and a standard gated turbo installed. The bad reputation is well deserved. Manifolds loosening, bad MPG etc. Truck mfr's can not use DPF to meet the 2010 requirements, it's just not possible. They now must use diesel exhaust fluid DEF which is also called urea, and selective catalytic reduction SCR. By getting rid of the DPF and it's inherent problems surrounding heat and it's need for maintenance they can now finally tune the engines they way they should be tuned - max power, minimum heat buildup and minimum fuel. That is why MPG on the big trucks are back up to 07 levels - or better in most cases by virtue of these changes and all new engines.
All in all, I'm happy I have only 1 Tier 4 Final machine.