Disclaimer: MINOR XML tweaks to make these trucks having a point at all. Do not expect something highly buffed or "can do anything without consuming fuel using AUTO".
The "Cheat Medium Tires" to match RU Heavy tire capabilities are available only for Level 20 as chains with reduced traction in mud and level 25 for the "special low pressure offroad". So standard gameplay from Michigan to Alaska is NOT affected, but these US trucks will have a point in later Yukon/Wisconsin maps.
New: Added an experimental (tweaked) three slot flatbed trailer. A bit "glitching" as the trailer is a yard too short for three cargos - but its ok and it has a point in gameplay at all.
Background: US Medium Trucks as the SD114, M916A, 2070A and the White Western have only access to medium tires, which offer as a 100kg tire HALF the grip as the HEAVY tires used on RU Trucks. Thus, the trucks working in Michigan and Alaska do not really work on muddy Taymyr and similar later US maps as Yukon and Wisconsin. Solution is simple - add some "buffed medium tires", these are with respect to "weight x grip" similar as heavy chained (OHD2) ones, the level 25 offroad tires are roughly MEDIUM OHDI times 2. So "Grip_Factor x Weight" is the same. Looks with "in game" stats better, but it practically isn't. The game information poor/average/good/exzellent is plain nonsense as it uses only friction but neglects the wheels weight being used for grip calculation too. If you have doubts - the vanilla BOAR has also MEDIUM tires. And despite a lot of power thats with 25 tons weight to move not working at all.
* SD114, M916, 2070A and WWS 4964 got this high level access to level 20/25 buffed tires. For use especially on Yukon/Wisconsin mud.
* SD114: total redesign as vanilla version is crap. Gave it "US Modern" engines from M916. A rear steer component as the original (https://www.youtube.com/watch?v=fAoIJOJt5lg) was integrated. Mass increased, was designed way too light. Its with rear steer way more nimble than a Voron D/Grad, but has (a bit) less less power & stability. True "Top US Medium", which rewards a clean driving style. AWD manually off can and will save quite some fuel.
* M916: Fuel capacity increased to 350l, long and strong winch. Now usable as a long range semi hauler. Still a one trick pony. Gooseneck trailer mod (https://snowrunner.mod.io/ir-gooseneck-pack) highly recommended to avoid frame collisions with "stock" 5-slot trailers.
* 2070A: Rooflights now made available, saddle low removed due to too frequent frame collisions and getting stuck with its own semitrailer. Suspension adapted for better drivability (less bouncy), hight & steering, center of gravity etc. unchanged.
* 5070A: New rooflights access, tires generally aligned with truckwidth. Blue minicrane for some space saving to make crane + flatbed + trailer work now even in corners (you may notice some sarkasm). No tirebuffs, available (dual) tires are plainly a useful selection of existing ones as the 3D model of that truck is incompatible with single rear tires AND proper placement.
* White Western: Except the additional access to the high level special chained & mud tires - that truck was very much ok, no further changes required.