Kenworth T660 vs T680 vs T700

You are asking some very inexperienced questions. Have you ever driven a truck?

 

No, assuming cross country is east to west coast over all the hills & mountains. 475hp & 1650+ torque would be a better fit. What are you using to move cars with now?

 

Agree. 550/3.58 is overkill.

 

Just get a T680 with standard Cummins 450.

I wouldn’t recommend the T700. Never drove one but heard they are awkward to drive.

T660 is a nice truck. Owned many of them.

T680 is what you want though. It’s the latest model and they don’t make the 660 or 700 anymore. That COULD affect resale value in the future.

I’d just get a regular 10 speed until you can afford a new truck then go with the endurant 12 speed auto. It’s far superior to the older autos. Just my opinions.