Have you ever wondered why your truck diesel is a straight six?

A STRAIGHT 6 IS THE CORRECT DIESEL LAYOUT
for motor vehicle use save for the straight 5 in Mercedes cars.

the geometry of this motor is perfect for diesel engine design

An old truck driver told me this.

Why are all Class 6 - Class 9 commercial diesel truck engines straight sixes?

CAT, Cummins, International and others?

Why was the Dodge Cummins 5.9 TD a straight six?

A V engine doesn't lend itself well to diesel designs for on-highway use.

Something to do with physics and the chemistry of diesel combustion.

V-shaped diesel engines at 45 degrees are great for railroad use however and railroads have been using them for nearly 100 years.

A 90-degree diesel V motor is a definite no-no in internal combustion engineering.

 

V-shaped diesel engines at 45 degrees are great for railroad use however and railroads have been using them for nearly 100 years. They fit nicely inside the narrow long hoods of train locomotives.

A 90-degree diesel V motor is a definite no-no in internal combustion engineering.

 

Which is why the 5.9 Cummins TD worked so well for Dodge light trucks. Scale-ability. They run buttery smooth.

 

The 45-degree V-engines in locomotives tend to have 12 to 16 cylinders. They have been produced both in 2-strokes and 4-strokes. The 45-degree gas-powered V twins in Harley-Davidsons used to shake badly.

 

a V-6 diesel?