The 6 month trip we made ( 5 Sept 2019 - 3 Mar 2020) was 17,000 miles and we burned 1900 gallons of fuel...... 9 mpg with many of those milles without the trailer....-
This is why I want the 3.55 rear end.... I am afraid of the 3.73 that I currently have.

 

Speaking of MPG's. I needed to fill the truck today and it was a special treat. When we are here at home we fill up at the King Soopers gas station near us. As we also shop there we accumulate discount points that reduces the fuel price. The sticker for diesel today was $1.99 and I had 90 cents off based on points. I put 35 gallons in the tank for $37. How sweet is that?

 

I sure hope so......

 

Yippeeeeee

How big is the tank in the F-450 ?

 

48 gallons

EDIT: I should add, when towing, I always keep two five gallon cans in the bed for insurance.

 

Thanks Steve......

 

As I said previously, I was terrified of the 4.30 rear end on the F450 and almost didn't buy it for just that reason. It turns out, that for my trailer weight, it is a pretty good match. If I still had the higher ratio that I had in my F350, I'm certain I would be spending lots more time in much lower gears, working the engine harder, and honestly, I'm not sure I could have made it up some of the hills we have climbed.

 

That's pretty much the exact same I'm seeing with my '17 SRW with 3.55 towing 13k lb. I generally run about 68 on the highway. I can squeeze 10-11 if I'm running 55-60 on side roads.

Same here! It's great having 80-90 miles of insurance in the back of the truck.

 

I tend to stick to 70 MPH or less.

If a higher ratio had been available (3.73) I would have taken it. As I've said in numerous threads on axle ratio selection, I want to give my truck every chance to easily tow. Should I move up to the F-450 - and it will be an F-450, not the F-350 DRW - I'll take the 4.30 if it's still available.

 

I have run enough semi trucks over the years that had instantaneous mile per gallon outputs as well as average. One thing I found right across the board is that if you are not in your top gear you are not making mileage no matter what. So the more time you can spend in your top gear the better your mileage is going to be. The higher rear end ratio is going to get you into high gear faster, keep you there longer and it's also easier on your whole drivetrain. Especially if you have to start out with that trailer on soft ground, the lower your ratio the easier it will lift it out of a soft spot. Even though with heavy power application I could back my trailer into a spot, I usually put it into low range and then I barely need to touch the gas. That is the advantage of the lower gear ratio, it just gets moving so much easier

 

Roy, If I may ask, what is your reasoning for wanting the lower gear ratio? It sounds like, for towing, most of us have concluded the higher axle ratio is a better option.

 

Sounds like Roy wants the best fuel mileage possible overall. He is towing at about 60-65% of the truck's capacity, so it shouldn't need the higher ratio to be most efficient. The 10 speed changes some of the conventional wisdom regarding gearing IMO. You have a very low first gear that is lower than 1st with 4.30 gears (truck never uses it except in tow haul mode) and a higher overdrive ratio. Plus a wider choice of gears in between.

 

Eric,

I've been wondering about how the 10 speed factors into the equation. Sally's brand new Explorer has the 10 speed and my son's F150 and his wife's Expedition both have the 10 speed as well. I'm guessing tranny ratios are available on-line but I have not invested the time to go look as yet. Do we know if the step ratios in the 10 speed are the same across platforms (e.g. Explorer, F150, Super Duty) or do they change to fit the vehicle and its vocation?

 

Eric I lol at your new Sig

 

I am looking for better fuel mileage........

Better mileage while towing would be nice..... But mostly when not towing.

The F-350 gives me the choice of: 3.55 which I had on my 2011 F-350 SRW...... That truck did fine.
The current F-350 DRW has a 3.73..... This does give me a smoother start and higher speeds climbing a steep grade.

If I went with a F-450, I have no choice but a 4.30 rear end. I am guessing that will give me worse mileage that the 3.55 I could get in the F-350 dually.