I recently made what might be a useful discovery for folks using the underscale 1/64-ish Lionel Tractors and trailers. If you want to do a bit of modernizing with your fleet or just need some more tractors, Kinsmart makes a 1/68 T700 Kenworth tractor that looks great and is quite affordable. The specific T700 model was only available from 2011-2014, but if you're reading this, proto-typicity is not your top priority and the T700 is very similar to a variety of semis used over the past 20 years or more.
Kinsmart on Left, Lionel on Right.
I should point out that there is no glass in the rear windows (I plan to add some plastic) but the price is right, the paint and detail is good and high sleeper roof does an even better job than the Lionel of hiding the scale difference. Two things to note about compatibilty with Lionel trailers.
1-You will have to drill the trailer hitch hole slightly larger. The die-cast metal is soft enough that this is very easy.
2- The trailer hitch is slightly taller than Lionel, resulting in a barely perceptible upward angle of the trailer. One could grind down the trailer hitch, but I wouldn't bother.
For sourcing, I found my tractor separately at a hobby shop for around 7 bucks, but Amazon sells a pack of 4 or $25 shipped and they can be bought with trailers for 10-20 bucks each or so.
