I towed 7K lbs 20' Vnose with my 3.21s and it was flat out awful. 8.1mpg. Cant wait to switch to 3.92

 

I get about 9.5 with my 3.55's towing a 4200lb travel trailer.

 

Depending on hills and winds, 5000 #s may be at the limit for 3.21. I have a 2WD CC with 3.21 and tow 3500 #s fairly comfortably and I've gotten as high as 12+ MPG and as low as 9.5 MPG. Tail winds push it up to 12.5 MPG but on average I get 10-11. These are not EVIC numbers but hand calculated at every fill up while towing.

 

Here is what I tow (with my old truck).



Used to get around 10 flat. Once I swap the gear, I'll post my new mileage. I'll be taking the same route (Barber MS Park) where I achieved 8.1mpg so most variables should be the same. In other words a good comparo.


I have no idea if a tune would help with towing. Havent done that yet.

 

I have a Superchips with tranny schedule option and have tried several tranny schedules. I can't say that it helps much at all for better economy.

 

That's pretty much my opinion also.

 

smokingJoe, looks like a Tundra to me?

 

That is definitely a Toyota Tundra. I wanted to get one but they looked too bloated and ugly. Other than that they are a beast whether you get the 4.6 or the 5.7. They also come with either 3.90, 4.10 or 4.30 axle ratios. Pretty beefy ratios.

 

That was my old truck. I sold it bc of the horrible ride quality. I posted the picture to show what I tow. When I towed the trailer with the Ram (and 3.21) I got 8.1 v 10.x in the Tundra.

I'm hoping the 3.92 will get the MPG back to 10.x