found an english description on another site (just google for this mod)

/quote
– F turns light
– 1 2 3 turn on
– Z puts promotions
– Controlled IC opens doors, windows, and other stuff
– controlled IC
– Functioning of the internal lighting
– Everything is fully animated
– running a speedometer
– Change Body Types
/endquote

the 5t and 10ts refer to the change of body height: 5t with lower panels and 10t at larger height.

That's right. German would be perfect (at least, it's a German Site), but English would be appropriate, too.
The only thing, I understand, is, that the Truck can hold 5t (5000l) and the trailer 10t (10000l). And even this is just a guess.

its nice to get a new mod - but can u please write in english ? i dont understand just one word.