Modern day it's the other way around
Actually it's not--it's just the external components/emission equipment that is a issue.
The engine below is a DD15-if it was stripped down to just a fuel /intake system there
wouldn't be much on it. Even so changing a cylinder head is not all that bad time wise.
Besides-Cummins doesn't even have a jake quite as strong as the DD series 13, 15, 16.
And there is very few diesel engines on the market that produce 1500 ft lbs torque at
975 rpm rated at 545 hp topping at 1900. The DD will pull down to 1100 rpm on a
grade, coupled with a DT12 AMT transmission at (99,000 lbs GW} it can average up to
5.9 to 6.1 per gal.
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Plus the lower ends {cranks} can run 1 million on a set of bearings.
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It's the over use of engine management software/electrical/emissions that's causing pain.
Talking with several DD people about this they feel it's overkill also, Corporate is as
Corporate does.