Yesterday, 08:30 PM #1
hugeredford
Registered User
hugeredford you said:
my dads 16000 pound freightliner w a 365 cat gets 12 mpg bobtail. Why can't pickup truck manufacturers make their trucks get better milage. Also I was wondering what kind of mpg your idi's were getting
I do not know my self but I think that industrial engines turn lower rpms. What rpms does your father's freightliner turn? I have found an improvement for lower rpms. I have found a 3 mpg improvement for running 3000 rpm and lower instead of 4000 and 5000 rpm range! Unless your engine is well balanced for that rpm (big $$$ or big skill) you are loosing lots of power/torqe to friction. 13 I think at 2000 rpm, 21 at 3000 rpm,31 at 4000 rpm I think. 44 at 5000 rpm, 58 at 6000, 77 at 7000, and 99 at 8000 rpms. Wow, even thoughit cost less to run a gas motor it still cost alot to turn gas motor rpms efficintly! You need a forged crank to hold up if you hang around 4500 + and $$ for balance. Diesels cost more becasue they have heavy forged rotating mass that you need anyway in a gasser if you get and real torque.
So is truck a gets 2 mpg and turns 5000 rpms and truck a gets 10 mpg mabe it turns 2800 rpm max!
I think it cost less to turn 1000-3000 rpm then 2000-4000 rpms!