My 99 Crew Cab shortbed K2500 with 4.10 rear end gets close to 17 not towing and about 10-13 towing 7000 lbs. We have a campground we go to that is at 6000 feet and we live at sea level so going it is almost all uphill and that's when I get about 10. Hope this helps some.
i had seen this talked about in another thread but could not remember what one, but how much does tire size affect fuel milege? i don't keep accurate account of my milege, but i know one freeway trip over a year ago, i got 18 mpg. i have recently paid more attention since a major drop in mpg (thinking it was related to faulty lift pump and/or thermo, but have only run one full tank since they were fixed). i figured it to be around 15mpg though, i do have 285 tires now which were previously 245's, i think. any help?
on another note, where to look to find gear ratio?
I pretty much average 13.5 empty with a pretty light foot. This is rural type driving with some mixed stop and go driving in town. I figured that was normal for a dually. But am thinking I am going to try a new thermo also and see if that improves mpg. Am almost positive everything on mine is stock in regards to sensors and such.
Okay, now these numbers that I see in this thread make me feel much much better about my truck. I read a different post a few months ago and most people were talking about how they were getting 18-24mpg! I felt sick at the 13-14 I had been getting, but now I see that most figures in this thread are right there where my numbers are at also. !!WHEW!!
I was getting just below 15 back in the summer, but now I am getting a little over 13. Last tank I believe was like 13.05mpg. No mods, 100% stock cept for a heavy flatbed that has to be costing me a mpg or two.
I have been averaging 14.5mpg in my truck in sig. That is about 80% Freeway driving with a light foot. I have 285s (I calculate in the difference in size) a lumber rack, and carry about 1000 lbs of stuff in the bed for work every day. this is on winter fuel so hopefully that # will go up come summer time):h
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