Our last truck was a twin screw, when we spec'd our new truck we went with the single drive axle. We saved a lot of money by not having to pay the 12% FET. We have not noticed any real difference in ride comfort, in fact with the air ride front axle the ride is smoother. We went from a 2000 model year Freightliner Century with a 96" sleeper, to a 2007 Western Star 4900 SA with a stock 82" Ultra High sleeper. We are very pleased with our decision with both the sleeper choice and going with the single drive axle. We also went from a 22" reefer box to a 16" reefer box, both with lift gates. The difference between the two trucks were very impressive, we will never go back to a Freightliner again. Even though both trucks are made by the same parent company, there is a huge difference in quality.
We went from a D to a C unit, we are a TVAL unit. We have not noticed enough difference in loads, including rates and miles, to warrent spending the extra money we would have paid for the 2nd drive alxe and the 12% in taxes we would have had to pay. We also save money because we have 4 less drive tires to purchase, we weight less, so we get better mpg.
We did a lot of research. We talked to fleet owners who ran C and D unit TVal trucks. We also sat down with the dealership owner, and spent hours comparing costs for building a D and C unit. We went over everything from weight, to horse power, to gearing for the transmission and rear end. We went over cost per mile savings vs posssible lost loads going from a D to C unit, our need for room in the sleeper, the 82" sleeper vs a 96" sleeper. Automatic transmission vs manual, which engine would be best for our needs, which extended warranties to purchase, which reefer to purchase, and which APU to use.
We feel we made the right choices. Our revenue has gone up, cost per mile has gone down, lost loads have been very few.
Before you decide if you want a single or twin screw talk to people who have both, talk to reputable dealers. Do tons of research. Our dealer helped us every step of the way, he let us make our own choices, and gave us the pro's an con's of our choices.
One thing I would suggest, and I am a very firm believer in, buy a true CLASS 8 TRUCK. This is just my opinion, and there will be a lot of folks who do not agree with this, but a class 7 truck and even the M2 Business Class class 8 trucks are made for regional use, and are not a long haul truck. I have talked to factory reps of the major truck brands, and they agree with me for the most part, especially for team drivers. The class 7 engines were not made for long haul applications. These engines are not million mile engines, as are the class 8 engines. A lot of expediters and expediter dealers swear by these engines and trucks. I have owned class 7 trucks, and learned through engine breakdowns, and rebuilds at under 300,000 miles, and truck chassis and wiring problems, I will never buy a class 7 truck again. But thats just my opinion.