The ETS gearboxes arent the best, so ive developed over 20+ gearboxes and retarders to choose from starting from 6 speed all the way to 22 speeds.
and fpr the engines, the Ets 2 engines unlock at high levels which take time.
mine only need level 1. with over 30 engines to pick from, u can customise ur trucks engine however u like

Credits:
BTRXmods