Ok guys, I need some suggestions here. My Dad has a '97 250 PSD Heavy duty 4x4 SC LWB. He has around 176K miles on it. He was going to trade for a Ranger to save fuel $$$. I talked him out of it. His truck is in great shape and has been maintained reguraly. I already told him to go back to factory tire size to increase fuel milage. He is currently getting 21-22 HWY and 14 Towing. Any other suggestions for this first Generation PSD to gain MPG's? I was thinking programmer but dont know which is best for his truck.
Something else too. You said you told him to go back to factory tires....if he didn't recalibrate his speedo when he changed tire sizes, his numbers are lying and that is why he can get 21-22.
I have a zf5 spd and 3.55s and everyday I get 15 to 16. Granted, I don't try to hard to make good mileage, but the biggest killer I have noticed is the new fuel. I used to get 18 and up everyday driving, when the fuel changed it dropped off hard.
All in all I can't even complain about 15-16. A 7500 pound gasoline rig that would pull as hard as my truck would probably get only 5 mpg at best.