On the Volvo subject...I just so happen to own the very first factory built Volvo 780 Condo straight truck 2008 model. It's a "D" unit. I got the factory to build this as a new model only if I agreed to thier spec changes. 1. Tungsten Alloy frame that's 4 inches bigger practically eliminating frame flex. 2. 14,600# Air ride front axle 3. Twin screw rears at 20,000# ea. This is a factory condo with a GVW 54,600# with an empty of 24,000#. 4. Fuel tanks (100 gal ea) are set back with 30% behind the sleeper. Any other stock Volvo tractor is a dealer stretch and will have the 12K front axle. This truck has a 297 inch wheel base. We ordered it loaded, 22ft Delta-Waseca Dry box, APU, liftgate, etc. It doesn't matter what class 8 platform you go with, if it has 2 axles and it's a "D" unit, you're probably over weight on the steer axle or pretty close even empty. Volvo does make a fine truck and the factory sleeper for us anyway has plenty of room. Certainly worth a look-see.