Western Star 9000 TwinSteer Trailer (AWD | AWS) 3.1.1 Mod
Install the .xml file manually into the initial.pak > [media] > classes > trucks folder to use in COOP or Subscribe for single player (SUBSCRIBE NOW WORKS!).
Adds a trailer hitch to the Western Star 6900 TwinSteer.
Added All-wheel steering.
Improved the steering angle on the back wheels slightly.
Same as Version 3.1 but works for subscribe (single player only)
Now there are three variations: AWD, 4WS, or Standard.
The AWD and 4WS versions have 400 fuel, costs more to buy, 300 kg heavier, selectable AWD and the trailer attachment.
The standard version is V1 and just has the trailer attachment.
The AWD version is V2.
The 4WS version is V3.
Siraij has also made a mod that is just the All-Wheel steering. Check it out here TwinSteer All Axles Steerable.
Works in COOP (if you install manually) but all people playing in the party needs the mod installed to be visible/work for everyone otherwise only you will see it/have it working.