Attention: TDR Forum Junkies 
Depends...
Driving habits rule mileage. I know guys who can't get but 15 out of their 12 valves, I have ridden with them and can attest to their lack of finnese as far as driving. Everything to them is either flat on the floor or full brake! Yes there are a few instances that the machine itself has problems, but on the average the old twelve valve is one of the most economical engines out there, if you were to put a power to mileage figure to them, they would out perform everything.
I got a high of 25 out of my old rig, but it was running in a blizzard at 45 in fourth for close to a hundred miles. This was a fluke and I know it, on the average I get twenty, this is in town mostly, highway 22-23. Hook a load to her and the numbers go down, but it has never run less than twelve, this is with 32' fifthweel, and boat behind her, pulling mountain passes. . The fun stuff. .
Driving habits rule mileage. I know guys who can't get but 15 out of their 12 valves, I have ridden with them and can attest to their lack of finnese as far as driving. Everything to them is either flat on the floor or full brake! Yes there are a few instances that the machine itself has problems, but on the average the old twelve valve is one of the most economical engines out there, if you were to put a power to mileage figure to them, they would out perform everything.
I got a high of 25 out of my old rig, but it was running in a blizzard at 45 in fourth for close to a hundred miles. This was a fluke and I know it, on the average I get twenty, this is in town mostly, highway 22-23. Hook a load to her and the numbers go down, but it has never run less than twelve, this is with 32' fifthweel, and boat behind her, pulling mountain passes. . The fun stuff. .
