I'm going to buy either the m11, or L10 cummins. I've been able to research the m11, but nothing on the L10. The trucks have about 500k miles on them, really clean, well maintained. I need help deciding the engine. Thanks.

 

I have an old L-10 in my motor home. 1990 Mechanical pump it is a great engine. I get 9+MPG pushing a 40 ft 34000 lbs motor home. mine is 300 HP
The M11 will get another 100 HP and drop the MPG in the same size motorhome to 6-7. I know of one truck that has the L-10 in it a fertilizer company still using it and it has almost 900,000 runs like new.