2015 Expy Final Gear Ratio upgrade - advise required

[bloodhound]

Not sure about HD Tow package...how can I find this out? I knew my MPG wud suffer after the tire increase, but I was hoping with re-gearing I cud View attachment 71860

Thank you!!! Can you let me know how you found this out? and just being sure...I'm assuming this is front and rear?
Also, if I am to go by the general formula - (New Tire size x OEM Ratio) / Old tire Size - I get 3.51 new gear ratio...

From here: https://www.ford.com/support/how-to...ow-do-i-find-the-axle-ratio-and-limited-slip/

 

[LokiWolf]

Yes, the gearing in the front and rear is ALWAYS the same. If it wasn't you would break things in 4WD. You do not have HD Tow based on that gearing.

Going to the Ford Factory 3.73 w/LS(Limited Slip) would help your acceleration and traction, but will not help your MPG. Your cruising MPG is worse because of the added resistance, both wind and physical contact(Larger Tire footprint). In addition your City MPG is worse because you increased your unsprung weight with heavier tires(It takes more energy to get the same results).