What are the Ground up dimensions of tractor trailer rig?

Well, the dimensions will vary by the power unit (tractor), and the trailer. A typical box trailer will have a maximum height of 13'6, and a max width of 110 inches, and be a max length of 53 feet. In some western states, trailer heights may reach 14'0, and some states permit the use of trailers 57' long, although their usage is very restricted, and they still have the same 41' bridge between the tractor drive axles and the trailer axles. In California, the maximum bridge allowed between tractor drive axles and trailer axles is 40'. Max allowed weight for a typical five axle setup is 80,000 lbs., although some states have heavier weights grandfathered in. The wheelbase of the tractor itself can be anywhere from 150" (even less for a daycab single axle unit), all the way up to over 330" for specialised units with the long, ICT sleepers... but these are atypical, and a typical power unit for long haul operations will more commonly have a wheelbase ranging from 212" to 265".

Output for a motor can range from 12.7 liters displacement to 14.7 liters displacement, and horsepower ratings can range from 350 to 625 (with the norm for fleet trucks being from 430 - 500 horsepower). Short haul day cab tractors may have lower displacement motors.

Transmissions can vary... normal configurations for a manual shift tractor include the nine speed, ten speed, 13 speed, 15 speed, and 18 speed, with nine and ten speed being the most commonplace for fleet trucks, while the 13, 15, and 18 speed transmissions tend to be more popular with owner/operators. Automatic transmission options include six speeds (these are very uncommon with tractor trailers, however.. the latest military line haul tractors use them, but you typically seem them on expedited vans and dump trucks), nine speeds, ten speeds, 12 speeds, 13 speeds, 15 speeds, and 18 speeds, and you have both fully automatic transmissions (such as the Eaton SmartShift), and you have the autoshift transmissions, which still use a clutch pedal, and are typically just a computerised shifting mechanism attached to a standard manual gearbox.