Am i doing something wrong?

[2whlzstan]

Originally Posted by dbark

Yes E85 is cheaper, but it is a lower octane level and you get some or a lot of knocking in your engine.

Actually, e85 has much higher octane, usually between 94 and 105, so knocking isn't an issue. It is very popular with the guys who run high compression normally aspirated engines and the high boost turbo guys. What it has less of is energy than normal gasoline, which is why we burn more of it.

[BobnVic]

I think I'll stick to regular gasoline instead of the e85

[sk734]

Originally Posted by lbrjet

Keep the truck and stop worrying about the gas mileage. Over time you will average around 8. I wouldn't even consider swapping the gears. That would be crazy. You already have a great truck, now enjoy it.

I agree. I own the same truck. It a great towing machine that is not in the repair shop all the time. That is worth a lot to me. I can also buy a new motor for about $4,000 if I need to. What would a new design motor cost? I have 73k on the clock and expect to get 250k+ before a motor change. I would keep it and run it. Happy camping

[Iwannacamp]

Originally Posted by beerfor2

One of the largest factors of MPG is wind resistance.

X2 But not the same...

Top alcohol dragster 3500 HP and 280 MPH 1/4 mile

Top fuel Dragster up to 10,000 HP and 325 MPH 1/4 mile

It takes 6,000 HP to gain 50 MPH in 1/4 mile ??

WIND RESISTANCE it's as strong as buoyancy

[Ejs4029]

My previous TV was a 2006 Chevy 2500 HD with the 6.0 gasser with the 4.10 rear...It was a 4x4 with 6 inch lift and 35 inch tires...I did all kind of stuff to it like cold air intake, Magnaflow exhaust and Super Chipped it.....Funny thing was it got around 8MPG towing and only 10 MPG solo the 20 inch Pro Comp Extreme Mud Terrain tires didn't help LOL so it didn't make that much difference when I was towing or not

It was stolen from my then local Chino, CA Sam's Club Parking lot back in 2015 never to be seen again RIP

[rracer5]

Originally Posted by Ejs4029

My previous TV was a 2006 Chevy 2500 HD with the 6.0 gasser with the 4.10 rear...It was a 4x4 with 6 inch lift and 35 inch tires...I did all kind of stuff to it like cold air intake, Magnaflow exhaust and Super Chipped it.....Funny thing was it got around 8MPG towing and only 10 MPG solo the 20 inch Pro Comp Extreme Mud Terrain tires didn't help LOL so it didn't make that much difference when I was towing or not

It was stolen from my then local Chino, CA Sam's Club Parking lot back in 2015 never to be seen again RIP

It was taken apart & reassembled again........in El Salvador.

[JPin AZ]

After reading this post I tried "to do it right". I pulled my trailer the same 120 miles as last time. This time I did almost everything in my power to stay in overdrive. I had trouble going 60 in a 65 mph zone. I was getting passed by everyone. First trip doing it wrong I got eight mpg. This time I got ten mpg saving three gallons of gas. 2nd trip I was loaded the most I have ever been and I believe the wind and weather was similar. The remaining 320 miles I was doing it wrong again, not one semi passed me.

[DouglasReid]

Originally Posted by JPin AZ

After reading this post I tried "to do it right". I pulled my trailer the same 120 miles as last time. This time I did almost everything in my power to stay in overdrive. I had trouble going 60 in a 65 mph zone. I was getting passed by everyone. First trip doing it wrong I got eight mpg. This time I got ten mpg saving three gallons of gas. 2nd trip I was loaded the most I have ever been and I believe the wind and weather was similar. The remaining 320 miles I was doing it wrong again, not one semi passed me.

Sounds like you may have been lugging your engine in OD. VERY bad for your engine.

Were you monitoring your Xmsn and engine temps?

Tow Haul is designed to keep your RPMs in the correct range to assist pulling and keeping both components from hurting themselves.

Saving a few MPG and burning up either is a false economy.

Just my .02

[rracer5]

Originally Posted by DouglasReid

Sounds like you may have been lugging your engine in OD. VERY bad for your engine.

Were you monitoring your Xmsn and engine temps?

Tow Haul is designed to keep your RPMs in the correct range to assist pulling and keeping both components from hurting themselves.

Saving a few MPG and burning up either is a false economy.

Just my .02

The constant shifting of the tranny can cause increased tranny temps. Not using OD and letting the engine run a little higher RPM allows the water pump to and fan to circulate more coolant through the radiator and the fan to pull more coller air through the radiator and tranny cooler thus, keeping both cooler.
In the long run, trading off a few MPG's is cheaper that replacing a transmission due to overheating.

[skacatz]

I tow a 7,000# travel trailer with a 3/4 ton Suburban, 6.0 liter w/3.73 rear. It’s a towing beast for sure. I average 9 mpg towing and about 13 solo. Towed the same trailer previously with a 1500 Suburban. The HD just feels more secure and in control and to me a little less mpg is a small price to pay.

[DouglasReid]

Originally Posted by rracer5

The constant shifting of the tranny can cause increased tranny temps. Not using OD and letting the engine run a little higher RPM allows the water pump to and fan to circulate more coolant through the radiator and the fan to pull more coller air through the radiator and tranny cooler thus, keeping both cooler.
In the long run, trading off a few MPG's is cheaper that replacing a transmission due to overheating.

Precisely!!, Gasser or Diesel the concept is the same.

Until you get the RPMs too high and burn more fuel to get thee, then it overheats due to excess fuel burn.

Find out what the ideal RPM range is and use Tow Haul and Cruise Control to stay there. For my truck, the RPM range is 1800-2400 with a sweet spot of 2100.

Of course pulling up hills requires downshifting to a lower gear to keep from overheating but always stay in that ideal range. I also use Manual Mode to control shifting to avoid constant up/downshifts.

With my 6 speed Allison I stay in M5 or lower, NO 6th gear (OD) EVER when towing.

Again, Gasser or Diesel same idea.

[Toma1953]

I have never had a 1/2 ton p?u for towing or daily driver. I buy 3?4 ton for both. Daily driving I get 20-25 and towing, I get 16-18 and towing a 31 foot SALEM. Of course it is diesel.

[dbark]

You never want to tow in overdrive, that gear is the smallest gear in the transmission and it can't handle the strain very long. So a little extra fuel economy isn't worth a new transmission

[JPin AZ]

Originally Posted by DouglasReid

Sounds like you may have been lugging your engine in OD. VERY bad for your engine.

Were you monitoring your Xmsn and engine temps?

Tow Haul is designed to keep your RPMs in the correct range to assist pulling and keeping both components from hurting themselves.

Saving a few MPG and burning up either is a false economy.

Just my .02

2000 rpm in OD at 60 mph is not lugging. 3000 rpm at 65 mph. Never even got to 200 degrees. 2003 5.3 Avalanche 3.73 359,000 miles.

[dugwms]

We have the same truck. Towing in Illinois, Indiana, Ohio, Missouri, Kentucky and Tennessee we average 8.5. We lock out 6th, set the cruise on 65 and enjoy the ride. We had a previous HD with 3.73 gears that was a bit better but not much. Sure makes a great tow vehicle though. Wind seems to be the worst enemy of MPG. Of course, the hills around Branson took their toll. At one time, the instant MPG said 2.

[moose074]

8 for a gas motor isn’t that bad not great but not bad. Towing my previous Northland TT with my Tundra 5.7 4:30 gearing I averaged 8 -9 depending on conditions and speed. First tank I towed on I got 6.5 strong head wind doing 75. Once I got out of Texas and speed limit dropped ( I like to stay within 10 mph of the posted limit when over 65) my mpg went up. It was exactly a 5k round trip and my combined mileage was 10. When I took my big trip last summer in my F350 6.7 3:55 gearing and my current 5er I traveled a combined 6569. 8 miles and averaged 10.1 for the trip. Just a side note since I know my current setup is taller and not an apple to apple comparison. I towed my previous TT with 4 ( two 1/2 ton gassers and 2 6.7 Ram and Ford) different trucks mpg usually never got above 9 while towing.
I also realize I am more like my dad as it seems I always have a head wind coming and going.

[PenJoe]

Originally Posted by bikendan

If not THE biggest factor.

That's very true. I get about the same gas mileage pulling a 16' cargo trailer as pulling a 12' flatbed utility trailer with a tip-down grated loading ramp. Significant weight difference, the one commonality is wind resistance.

[Tundra 2014]

It does not seem too far out of line. Just curious, have you weighted your trailer? My FR V-front weighed 875 more than sticker weight. Mine has the Emerald pkg. w/ electric jacks, second air and other options. Tongue weight listed at 875, actually over a 1050, w/ 2 -30 lb. propane tanks and group 27 battery. As others have said, the 6.0 GM motor is not known for great milage. My boss went from Ford to Chev. 6.0 and complains about the 9 MPG he gets empty. I went from 1/2 ton to 1 ton, much better towing experience w/ trailer.