Thank y'all!
@coolusername, nope, they don't steer, only lift. It's kinda hard to explain, but Russian weight laws are very dumb. Basically if you have 4x2 plus 3 axle trailer (5 axles), your gross weight is 40 ton max. But if you have 6 axles (4x2 plus 4 axle trailer) you can weigh 44 tons. Normally 4 axles group with 4x2 tractor would make drive axle overweight, so trailer manufacturer puts that axle forward. But it's not steerable to reduce cost.
So drivers lift trailer axle when doing tight turns. (and some drivers, who don't really care, always keep the axle lifted and only lower it to go through weight station)
@Arnook thanks! I wanna try it myself first to learn (i'll PM you if i get stuck somewhere

) TBH this is my first modded ownable trailer. It's been a while since i modded trailers at all