Detroit Diesel 12.7

I've been driving a Freightliner Century with a 12.7 and we average 8.1 mpg. The weight I'm seeing on the BOLs are anywhere from 4k lbs to 20k lbs, not too heavy. The owner of the truck could never keep the AC running and planned on installing a roof air unit instead but did not get to that. So, due to the AC issues, at the time of the bullgears repair, he had the mechanic remove the drive gear for the AC. He credits the good MPG and quiet running to the removal of that AC/drive gear. This will be the 2nd truck i've driven with a 12.7 and it does seem to run quieter and nicer than the truck i previously drove.

 

I wrote a longer reply but yes thats what he said, he could not keep the AC running and thats why he had the mechanic remove the drive gear for AC. I guess his plan was to install a roof mount AC unit, but he found another truck with a bigger, standup sleeper (he's like 6ft 5 or somethin) and I can see why he wanted a bigger sleeper.