I have a 4.10 gear ratio in my dually and was wondering what you guys would recommend for a daily driver. I really only tow 3-5 times a year, and pull a 11000 pound 5th wheel.

I had a 2003 F250 5.4l gasser and it had the 3.73 rear end. It pulled the camper, but was straining the motor pretty hard up the hills. That's why I bought this truck.

What gear ratio do you think I could get away with in this type of situation? I was thinking maybe a 3.55 for better fuel economy, but don't know how much that will affect me when I go to pull the camper.

I am planning some mods for this truck down the road. Maybe a chip, dp, exhaust, stage 1 injectors, and the 6637 intake. That's all I would do to it.

So, what do you guys think? Should a 3.55 gear ratio be ok across the mountains. When I say mountains, I mean the NC Tenn mountains. Thanks in advance.

 

We are talking RPM's and fuel consumption here.

How many RPM's at 75mph? - Ford Truck Enthusiasts Forums

Options would be a 3.73 or 3.55 ratio.

Also, do you add any 2 cycle oil or similar in the tank to improve mileage?

Can you take off the extra wheel in back while not towing and run 2 wheels instead of 4 ... might help.

 

This is a quote from the other forum that you linked to.

That's what I am looking for on the daily driver end. I'm just wondering if a 3.55 would still pull ok.....

Thanks.

 

3.55 would probably pull decent. Then again the route you need to take to Tn. right now because I-40 is closed has a real long pull on it. 4.10's even get pulled down on that one.

If you have 2WD or don't plan on using 4X4 when towing you could swap the gears when you tow and back for DD.

I have a 3.73 set laying in my shop right now.

 

I think 3.55's would be find for you

 

When I had 3.55's in mine, I towed my camper (on 2 different trips) to both coasts. First trip was 4500 miles and went through the Rockies. Second trip was 7500 miles and came through from Fredericton, New Brunswick to Boston and on through Chicago on my way home. Worked fine for me. Last summer I was pulling the same trailer even with the 37's and 3.55's. I'm likely putting them back in once I have the gears for the front.

 

I pull a 9500 lb conventional trailer with a 3.55 rear end, take it over the rockies all the time and it does just fine, there are times I wish I had a 3.73 or a 4.10 but those are only when I'm going up a 7 or 8 % grade, I just drop down a gear and take it nice and easy. I get good fuel economy with the 3.55.

 

What kind of fuel mileage do you get with 3.55's?

 

20-22 running without the trailer, towing....depends on speed, if I keep it at 60, I can get 14-15, 65 will drop it down to 13, 70 drops it down to 11-12, I usually set the cruise at 60.

 

So I guess it does not matter what gear ratio you have above 60MPH.

Cause at 60 MPH in my 4x4 crew 4.10 gears I get over 20MPG but above 70 MPH it goes down to 14-16 MPG. Empty load.

 

Well, I have a 2wd dually and most of my trips are down to the beach. I have just recently started going north instead of south. My truck is more of a daily drive than a hauler. I think I would benefit with the 3.55 for the fuel economy and I'm not a racer either. I was even considering the 6 position chip from rosewood and could maybe make up some of the pulling power that I would lose with that. Thanks for all your input.