Is there a correlation between engine size and fuel consumption?

[Peterbiltatruck]

Does anyone know if there is a correlation between engine size (displacement) and fuel consumption?

[harishw8r]

There certainly is. I operate 500 hp vehicles of all brands and there is definitely differences between the different engines. Take Volvo and Mack for instance. Mack has a 13-litre and Volvo has a 16-litre engine in the 500 hp segment, and Mack offers a better fuel economy. The VNL’s is the worst.

Other factors like gearbox also affect the fuel economy. The Cascadia’s is the best in the game, better than Mack, despite having a 15 litre engine. I compared Mack and Volvo since their gearboxes are almost similar.

(Note: All these results were based on my experience)

I believe the engines also have weight data in the game. Someone can confirm this.

[FierbetoN]

They have volume and a consumption coefficient, but I haven't seen the latter being used.

[Steve Pitts]

Yes, as long as you are playing with realistic fuel consumption turned on, according to Max of SCS on this thread: Fuel economy

[Gazer75]

Biggest difference is displacement really. A 15/16 liter engine will use a lot more than a 13 or 11 liter.

Though hauling the really heavy loads with an MX-13 will probably be around the same as a bigger 15/16 liter as the smaller one will struggle more and you'll be in a lower gear more often.