SLOVAKIA
There doesn’t appear to be a dedicated site with truck related info on Slovakia so here are some bits and pieces I picked up when I was there a couple of weeks ago:
Vignettes are required for all vehicles.
Cost for a vehicle over 12t (yellow sticker) is 10€/day. The vignette can be purchased at the border or at service stations in cash in Euros. Euros are widely accepted, so there is no real need to change up any currency.
A daily vignette is valid for 24 hours from the time of purchase. The time of purchase is indicated on a control slip which should be detached from the vignette and be retained for inspection if required. The vehicle registration number must be entered onto this control slip. The vignette itself should be stuck on the right hand side of the windscreen. Camera enforcement in operation.
Dipped headlights are now required at all times.
And finally, the biggy:
No overtaking for vehicles over 3,5 t on ALL Motorways and dual carriageways in the whole of Slovakia 
This is signed up at the border but there are no repeater signs anywhere else on the road network.
Usual rules apply: Ignorance is no defence 