With the uphill portion of my 'Streets country road finished, I decided to take a break from building roads and scenery and build vehicles for a while. This little puppy worked out well - looks good and runs very well. I've made (and will make again) some 18-wheelers, but I thought it would be fun to motorize one of the piggybacks from the recent Lionel PS-4 with REA piggybacks.
This is an entirely scratch built chassis - both tractor and trailer, although I used axles and some center pickups for 'Streets vehicles. Motor is definitely not stock, but the biggest flywheel motor I could find, and it is geared 3:1 reduction.
Anyone into 1:43 cars and trucks will recognize the tractor's cab, taken from the nearly ubiquitous New Ray Mack truck, but when Lionel ships the REA tractor trailer I am waiting for (6-37850) I will install the cab from that tractor on this.
This puppy runs very well and and handles the 4% uphill grade without problems - it will even start cleanly from a stop when headed uphill, too. It handles my city streets but does not like D16 curves at all.
I'm having fun and will make at least one more tractor trailer and a intercity bus (greyhound) as opposed to the city buses I've made for my downtown streets, before going back to completing the country road.
Sorry the videos are short and a bit shaky - I had to operate the camera in one hand while the power supply in the other.
any plans to make a firetruck...
I'll bet that thing could fly if you opened it up, imagine the horsepower to pound ratio! 
