I had a 21 RST with the LM2 3 liter diesel, I was averaging 27.4 MPG over the almost 2 years 4 months and 21K life I had it (retired so no daily commute). I wanted a Trail Boss but I wanted the diesel more because of the fuel mileage and no DFM/DOD, but it wasn't available in 21 in the TB so I got the RST because I needed a new vehicle then and what a great truck that was! I knew in time the diesel would be released in the TB so I patiently waited and in 22 sure enough it was, but they also released the ZR2, now I was torn again. I knew in time the ZR2 would likely get the diesel and by then they had the new LZ0 with some upgrades over the LM2, so again I patiently waited. Then the news hit, the 24 ZR2 would come standard with the LZ0 and I plotted my switch, I knew this day would come so I had kept the RST just like brand new, not even a scuff on the all weather floor mats, and just a couple of dings in the painted front bumper which I dutifully kept touched up with my free touch up paint from the dealer. When I went in the dealer appraised the truck I had paid 52K for (7.2% off MSRP) at 37K, I haggled and had them look the truck over with a fine tooth comb and they finally made it up to 42K and I said DEAL! By that time I already had negotiated the 75K sticker down to just over 69K and change so the long day and all the work made it all worth it in the end. This truck doesn't get the MPG's the RST did due to the lift and no front air dam, but I am averaging about 24 MPG over the last 2645 miles and 110 gallons of diesel so I am happy enough with that. I hope you have a long and happy life with yours! Happy motoring my friend!!!