First long pull

dolbsss wrote:
I have a 6.0L 2500HD pulling a Jayco 284BHSW(6000-7500lbs). Drove to Michigan last week and back from Columbus Ohio. I got about 8.5mpg with a lot of stop and go traffic in Michigan thanks to construction zones. When I pull my landscape trailers(open air) of similar weight but less wind resistance in the city I usually do better, maybe 9.5mpg. No trailer in the city 11ish, no trailer road trip around 15mpg. I think the wind is a huge factor obviously. Would love to make myself more aerodynamic while towing. I imagine 5th wheels would be worse.

The 6.0 is a thirsty motor...

early 99 or late 99?

Tuner, turbo wheel, test and fix any turbo pressure leaks, check for any brakes hanging, etc.

The 7.3's can give many, many miles and years of strong, reliable service, but they NEED regular maintenance. Much more than a gasser ;)

I have a 6.0L 2500HD pulling a Jayco 284BHSW(6000-7500lbs). Drove to Michigan last week and back from Columbus Ohio. I got about 8.5mpg with a lot of stop and go traffic in Michigan thanks to construction zones. When I pull my landscape trailers(open air) of similar weight but less wind resistance in the city I usually do better, maybe 9.5mpg. No trailer in the city 11ish, no trailer road trip around 15mpg. I think the wind is a huge factor obviously. Would love to make myself more aerodynamic while towing. I imagine 5th wheels would be worse.

RandomAbstract wrote:

BTW, I get 8mpg with a 5.7 Hemi towing 4,000 pounds. But I am traveling 70 mph crossing the plains into a headwind to get to the mountains.

Towing 3500lbs with a 5.7 Hemi and I average 10.9 mpg if I set the cruise at 70mph. Back that cruise off to 65mph, the truck will drop a gear less often, raise me to 11.9 mpg (mostly western PA and east, which is a bit hilly).

I haven't taken the TT west, but I imagine I could squeeze better than 12mpg on the flats....but not much more.


Drive until tank reads 1/4...hand attended at gas stop a $100.00 bill...hope to get some change. Current prices leaves enough to buy lunch and snacks. In 2014...it didn't fill the 32 gallon tank.

Were you in hills or flat land?

I always got around 12-13 average, as high as 15 in south Georgia to Florida and as low as 9-10 in hills and through mountains. I have a 7.3 automatic 4 wheel drive.

2012 270 FK Coachmen empty wt 7204 loaded weight usually near 8500 scaled pds.
I averaged 12.3 mpg for 1800 miles pulling from Harlingen, TX to WV. Tow speed 50 - 65 depending on the terrain and traffic.
The Tundra I had pulling the same TT was high 7's low 8's.

Yes, I think you should be getting better mileage. I had a 2000 F250 7.3 and I remember routinely getting right around 13mpg towing a 21ft travel trailer. This was hand calculated over many trips (no "trip computer"). Note: this was with a 2 wheel drive truck, but I wouldn't think that would make that much of a difference.

I may have missed it, but what transmission and rear end gearing does your truck have? My truck had the 3.73 rear end I think (been awhile now).

Also, has your truck had ANY "mods" to the engine? Chipped, different exhaust, different intake, etc?

Tires - I was running stock "all season" tires. If you have "off road" type tires, the tread can reduce your fuel mileage a little. Are your tires and wheels stock / original? Anything different will affect mileage. Also, are they fully inflated?

Fuel - the last time I bought diesel, it was just as the switchover to the new diesel was occurring, so I was measuring my fuel mileage using the old diesel. I don't know if that makes a difference, but usually anything government mandated makes things worse.

Driving style - Driving around town will dramatically lower your mileage, so make sure you fill up just before hitting the highway, and refill / check mileage as soon as possible at the end of the tow.

Passin Thru wrote:
I get 9.8 with a 2006 Chevy and it doesn't use Urea so should be better. your's seems normal. I tow at 67 and run N Va to either Co, Tx, or Ok and back plus Wrn NY state. Don't worry about fuel mileage, you're towing and your motor isn't broken in.I will challenge anyone to hook on my Arctic Fox and get better mileage at the same speed.

How many miles does it take to break in a 1999 motor?

dieseltruckdriver wrote:
There are too many people concentrating on the weight of this or that trailer. The aerodynamics of each individual trailer will make more of a difference than the weight. A bad wind day has had me as low as 7.5, and a good day I got 12, once. Wind always makes more difference than these small differences in weight.

Before you start arguing with me, understand I drove hazmat tankers for 17 years. There was a work day I got better mileage loaded than empty.

very very true. if you hold a constant speed on flat ground weight actually has almost no effect on mileage. It's rolling resistance and drag that dominate by far. BTW engine speed loss is also a square law effect, and wheel bearing friction losses, so going faster not only is drag affecting you but so is the increase in engine rpm and bearing losses.

areodynamics are a square law effect. Weight only comes into the equation when you are starting and stopping or going up and down hills. and then weight is a linear effect.

so, keep a constant speed on the highway when the terrain is flat.

Now, when going over mountain passes or on rolling terrain weight does come into play, but again, not near as dramatic as drag and wind.

stickdog wrote:
This time of year your running government mandated B20 biodiesel. Milege will improve if you can find straight No.2. Ha,ha.

hugh???? what gov't mandated B20 bio, surely you are joking. B5 in some states, but that's it.

but what I can say is that B20 has virtually the same BTU content/gallon as number 2, higher cetane rating, better lubricity, and in oregon $.30 less per gallon. When I run B20 in my duramax I don't see AMY measureable difference in mileage, up or down.

As long as the vehicle is approved for it no reason not to run it IMHO