MPG/Trip Report.... - Diesel Forum

lowerd96 · 10-27-2008, 01:17 PM

Well we took our first major trip with the new '08 this last weekend to close out the trout season in the Eastern Sierras. 4 people and a dog in the crew cab, with 4 days worth of food, beverage, etc....+ camping/fishing/4 wheeling gear. Truck had roughly 600 miles on it before the trip. Filled up here in San Jose until I could see fuel and headed east to 108/Sonora pass on our way to Walker, Ca. Very steep pass, with one section hitting 27% grade I believe. Anyway, made it to Walker using just a little more than 1/4 of a tank. About 220 miles, lots of hills. Not too bad! Fished up and down Hwy 395 from Walker south as far as Bridgeport area. Some dirt roads and 4wd usage as well. Sunday we packed up and headed north to catch Hwy 89 over Monitor Pass, Markleeville area on our way to Hwy 88 where we fished stretches of the Carson River. Then back down 88 through Jackson where I filled up for the first time since leaving home. Computer said I had 50 miles to go, so I topped it off all the way until I could see fuel again, and ran the numbers. I added 35 gallons to the tank, with 517 on the trip meter, for a 14.7 average. Jackson is about 120 from San Jose, and the needle is still on full, so maybe it's going to get a little better on this tank! For the record the first tank I calculated in this truck prior to this trip, was 12.3....ouch! Lots of stop and go on that tank, so this was the first one out on the open road. 14.7 is not too bad for a crew cab that fit everyone comfortably, plus all our gear and a dog. The truck has endless power in the hills, and the trans was real nice holding speed coming down passes. Much like my 6 speed in my 7.3L. Plus getting in after a long day fishing in the cold Sierra water and putting the seat heaters on as we headed back to camp made it all worth it!!!! Overall great trip, truck was flawless and we are looking forward to more adventures in our 6.4....

CMB430 · 10-27-2008, 01:29 PM

You need to update your signature block so we know what your SD is! Sounds like you had a nice trip. I have been averaging 15 mpgs, down from 17 mpgs, since they put a new DPF in mine and reflashed the computer a total of 3 times. Sort of frustrating, which is why I bought a Jetta TDI...It can hold me, the wife and the dog plus some small gear and gets over 44 mpg!! My truck is going to get one heck of a workout going to the hunting camp in a couple of weeks.

lowerd96 · 10-27-2008, 04:29 PM

Updated the sig line! Thanks! I feel like MPG is going to steadily improve, I hope to see 16 out of this truck empty at cruising speed. By the way how do you like the 6 speed behind the 6.4? Just curious, I swore I would never buy anything but a stick shift truck, but the wife had other ideas, so we got an auto...

CMB430 · 10-27-2008, 07:15 PM

It sucks when starting out, especially when on a hill and having a trailer attached. But once I get into 3rd gear, I can run her all the way up to 60 mph if I need to **** and get. The cold weather really makes her miserable, and that anoying slapping sound like the U-joints are loose is still present, but I just prefer manual transmissions. I have had the following: 2006 2500HD 6.0L 5spd x2, 2008 Frontier NISMO 6spd, 2004 Dakota 5spd, 2003 Blazer ZR2 5spd, 1999 Silverado 1500 4.3L 5spd...and the list goes on. Some day I will be like your wife! But I just bought another...

T210DRVR · 10-27-2008, 08:49 PM

Just drop 156 miles to coast and back with my 12 valve Cummins. It took 7.2 gallons to fill up. I'm afraid the ride wasn't near as nice as the new trucks, but I can't hardly get less than 20 mpg unless I'm towing.

compman72 · 10-27-2008, 10:15 PM

I just picked mine up in Memphis last week and I had 2000 lbs in the bed and I was getting 14 mpg

and that is at 1300 miles on the odometer.

dieselmankane · 10-27-2008, 11:18 PM

I love reading threads like these. We need more positive threads, thanks for letting us know what's up. I have faith in the 6.4 so far. This is just such a clean running truck, smooth and quiet as well. This 6.4 engine seems far better than my previous 6.0 so far. I have mostly heard good things, especially from what I hear from guys who have had there 6.4's for a while with no issue. The only issue i have with my truck is that the rear cup holder that folds down does not stay clipped in, but the dealer will fix that I am sure.

washie · 10-29-2008, 07:19 AM

Just got to Fla. from Maine, 1756 miles. Average MPG 8.5, towing a 14,000 # fifth wheel, Cruise set at 62 MPH most of the trip. LieOmeter said I was averageing 9 to 9.5 MPG. I find the Average Mile Per Gal meter is about 1 mile per gallon off no matter if I am towing or not. Oh by the way 4:30 rear end. But she never slowed down all the way hills or not. Love my Truck!!!!

lowerd96 · 10-29-2008, 02:31 PM

Quote:

Originally Posted by T210DRVR

Just drop 156 miles to coast and back with my 12 valve Cummins. It took 7.2 gallons to fill up. I'm afraid the ride wasn't near as nice as the new trucks, but I can't hardly get less than 20 mpg unless I'm towing.

My trusty old 7.3L gets a solid 18, but I would much rather ride in the new one. The 08's are so quiet, smooth and fast, 3-5 mpg's less is a fine trade off for me!

MT_flyfisher · 10-29-2008, 03:07 PM

Quote:

Originally Posted by washie

Just got to Fla. from Maine, 1756 miles. Average MPG 8.5, towing a 14,000 # fifth wheel, Cruise set at 62 MPH most of the trip. LieOmeter said I was averageing 9 to 9.5 MPG. I find the Average Mile Per Gal meter is about 1 mile per gallon off no matter if I am towing or not. Oh by the way 4:30 rear end. But she never slowed down all the way hills or not. Love my Truck!!!!

I got a hand calculated 15.3mpg driving my F450 4x4 with the 4.30 rear from MT to PA several weeks ago, not towing anything but with about 1,000 of misc items in the back seat and truck bed. My LieOMeter is always higher than actual at every fillup, sometimes as much as 2mpg or more. My truck is a JOb #3 with just over 9000 miles on it.

KRCOOK · 11-03-2008, 10:12 PM

Quote:

Originally Posted by dieselmankane

I love reading threads like these. We need more positive threads, thanks for letting us know what's up. I have faith in the 6.4 so far. This is just such a clean running truck, smooth and quiet as well. This 6.4 engine seems far better than my previous 6.0 so far. I have mostly heard good things, especially from what I hear from guys who have had there 6.4's for a while with no issue. The only issue i have with my truck is that the rear cup holder that folds down does not stay clipped in, but the dealer will fix that I am sure.

I bought my 08 in August and after the first 1000 miles, towed pretty aggresively with it on and off for the next 5000 miles. This was mostly out of necessity but also I believe in breaking in these engines aggressively and quickly.

At about 1000 miles, my wife towed a 4500 lb horse trailer in 70 mph winds and got about 9.5 mpg. Nothing to crow about but it was a good break in workout. Towed about 1500 miles with that trailer and also towed a 10k bumper pull 32' camper 1500 miles round trip from Dayton Ohio to Tulsa Oklahoma and averaged 7.7 hand calculated (lie-o-meter said 8.2). All this should have been pretty good break-in.

Today, the truck has 6000 miles on it and this weekend, I took it on an 80 mile trip on two lane highway with cruise set at 62 mph and the computer said 19.2. These were fairly flat roads (127 from Greenville to Celina Ohio). I am pretty confident that I had no regen during this short trip and granted, this is not hand calculated. But when I have calculated it, it was never off more than 0.5 mpg. I have seen a few other people posting about 19+ mpg at 55-60 so I think this is entirely possible.

The frustrating thing about this truck is how fast and how far mpg drops when you get into stop and go driving. The 99 dodge I had came with a 4 speed automatic (the slush box) which I upgraded to a Goerend torque converter with a much tighter fluid coupling. I think this makes a huge difference on mpg in city driving. I have been very surprised reading this forum and several others, there is almost NO discussion of the torque shift transmission in these trucks. IMO the fluid coupling of the torque shift is NOT very tight and is a factor in the low mpg in city driving. Don't get me wrong, I LOVE the rest of the transmission. Towing 10k lbs through the hills of southwest Missouri, downshifting to maintain 70 mph going up hills was smooth as silk in tow haul mode. But, starting from a dead stop sometimes seems like the truck doesn't really start to move until you hit 2500 rpm and then the boost is 25-30 and there goes your fuel economy. In the dodge, 2000 rpm set you back in the seat (granted, this was with the after-market TC). I have assumed that some of the "looseness" of the torque shift TC is by design because it is mated to a V-8 diesel which does not develop peak torque until 2000 rpm vs. the new dodge tranmission and TC which appears to have a much tighter fluid coupling. But mated to the cummins which develops peak torque at 1500 rpm you can get away with this. Still, seems like the torque shift could be tighter.

But, if all I wanted was a truck to pull with, I would have bought an 08 dodge. As I have seen stated on this sight several times, nobody can hold a candle to the ride and cabin design of the Fords. This is one beautiful truck, inside and out. I love it! I just need to get used to higher rpms.