AKDSLDOG

110 Miles a day at 75-80mph = 19mpg..... Under 2000rpm's (67mph) I get close to 23mpg. I can never stay under 75mph though. ;D

mic646

Around town I get about 14.5 mpg. <br>Freeway speed 70-75 about 14.5 mpg. <br>Two lane road speed 55-60 about 18.5 mpg.<br>

phox_mulder

Last summer/fall before winter fuel, I was seeing 16.5 average with my 2002 auto with 3.55 gears.<br>I saw a high of 19.8 pure highway, 70-75mph.<br>this was still under 10,000 miles without towing anything, hardly even broken in yet.<br><br>Winter fuel, averaging 14.9.<br>Currently 16,500 on the odometer.<br><br>Haven't had my huge tires long enough to get a good reading, but maybe about 14.0 on winter fuel.<br><br>This is probably about 60/40 highway/city miles, trying to keep it under 70mph.<br><br>Winter fuel should soon be a memory, only can go up from here, hoping to break 18 average with 34.5 inch tires.<br><br><br>phox

manic_mechanic

so is anybody running an aftermarket overdrive to bring the rpm's down for fuel milage?? will they take the power after mods.??<br> i'm not inpressed with my milage at 18 as girlfriends 4x4 chevy gets 17 and my '73 power wagon ith 39's and a 440 gets 14mpg. and these figures are at 70-80 mph.

manic_mechanic

yea, i'm afraid your right. seems like after 70mph fuel milage just isn't possible. need to be low to ground and good aerodynamics.<br> when i was trucking i upped the HP in my kenworth by 100hp and picked up 1.5mpg but couldn't hold that milage after 74mph or so.

TNoutlaw

My, 01 daully with 4:10 auto tranny gets 14.5 dragging up to 16.5 just running at around 2000 rpm at about 63mph . I was disapointed at first but think about it ,your running a heavy duty truck . What kind of mileage was trucks getting 5 years ago counting dodges.

GrandpasRam

My old Cheby '89 1/2 ton 4x4 got 17 - 18 also, but not when towing! Remember what the diesel is for in these heavy duty trucks - towing weight. My Cheby got 8 mpg towing a 4000# trailer (it had the trailering package) :'( The diesel does a lot better (almost 45% better), and doesn't lose it on minor hills or headwinds. The '78 GMC 1 ton I had years ago (gasser) got 12 empty average and 14 pure highway. I really like my CTD better than anything I've driven in the last 35 years of driving. ;D ;D

Trickytrae

Wow, now I know why I drive a 12valver, and I cant wait to put the gearvendor on.

Srigs

My 97 gets 18 to 20 arround town, 23 to 25 on the highway @70 to 75 and 16 to 17 towing with 3.55 gears.

HC

Jones0027,<br>I get better mileage than you! Now, &quot;the rest of the story&quot;:<br>You bought in June, so you weren't broken in during last summer's driving. This post is in April, you're in Illinois, so it's probably just warming up in your parts now, this will be your first summer with a &quot;broken in&quot; truck. When temps rise above 60 and summer fuel is in the tanks, you'll see your best mpg. Oh, did I mention I often stay below 70, somemtimes even below 65 mph, with lots of steady cruising?<br><br>You'll probably be above 18 during the summer even if you do nothing different. If you set the cruise at 73 mph, you'll get there almost as fast, and probably be above 19 mpg. Drop to 70 mph and you'll be 20+, and have the satisfaction of not even tapping the brakes when you see the Highway Patrol. (I love maintaining speed, smiling and waving.)<br><br>I wish I could get 18 at those speeds! The way I see it, these trucks get &quot;slightly&quot; better mpg than a lightweight 1/2 ton truck (almost cars, IMHO), can last 3 to 5 times as long and still be reliable, and have unmatched capability if you ever want to hook up a big trailer. It's the ultimate &quot;speak softly and carry a big stick&quot; truck.<br>

furious70

so 20-22mpg with an empty 01 HO 2500 4wd at 70-75 with 3.54's would be exceptional? I'm looking at such a truck right now, but I don't pull more than 8000lbs very often, and my current truck handles the loads fine, and will get 22mpg @ 75mph all day long empty....

gs

around town towing 10000# i get 16.5 and on the highway unloaded i get 18.5-20.5<br><br>but your truck is at least runnin mine broke last night just quit gettin fuel

Diesel fitter

[quote author=Jones0027 link=board=5;threadid=13584;start=0#127846 date=1050329018]<br>Gentlemen,<br> Rerturned from a trip and checked my mileage. 468 miles on 26.34 gallons of diesel calculates to 17.7 MPG. :'( 400 of those miles were all highway at 75 to 80mph with no load. Is this about what everyone else is getting? ??? I'm not BOMB'ed at all. I guess that I expected a little bit better. : Please let me know. Thanks. <br><br>[/quote]<br><br>I too get around the same mileage. I can't slow down though, and I know this would help. When I tow my trailer (around 9700 lbs) and keep the speed between 75-80 my mileage drops deown to near 10 mpg. I only have around 9k on it and I know should improve a little with more miles. I have never gotten any better than 18 mpg empty!

sdr650

I only have 2300 miles on my 03 3500 Dually, and when empty I get 20 mpg @ 55mph, and with my slide in and trailer behind me I get 14.5 mpg. The key thing is for every 5 mph I increase my speed, I lose 2 mpg. So I can't really see where anyone is going to be getting any outstanding mileage when traveling 70 -80 mph as in the past few posts. It's interesting that it only takes a few mph to drop that mileage though.