The Lionel Trackmobile is a nice looking little engine but it will only pull a few cars.
There is an article in the Oct Trains Mag on the real Trackmobile. That engine will pull up to 60 cars.
The couplers lift the front and rear cars about an inch off the rails and shift up to
90000 pounds to the Trackmobile to add traction.
Maybe Lionel could replace traction tires with lifting couplers.