Why do American semi-trucks (18 wheelers etc) exclusively use inline 6-cylinder engines, no matter if it’s a Mack, Detroit Diesel, Cummins, or Volvo-built engine?

Question

I get why they are diesel, but why are they all of the inline 6-cylinder configuration? Why not V6 or straight 8 or freakin huge inline 4-cylinders?

In: 715

Answer 1

You can scale the shit out of an I-6 and still be in perfect balance (as un not shaking itself to bits). The challenge is packaging – they are long engines, they won’t really fit in a modern car transverse application – so you see them in rwd applications.