I'm new here, looking at possibly picking up an ecoboost F-150. Looking for a Crew FX2 with the 20 inch wheels. My local dealer has one with the 3.15 gear ratio, I usually don't get the lowest gear available but I don't do much towing anyway. My question is does the short gear make the truck a lot slower then the bigger gears would? I know usually you get a mile or two more per gallon on the highway. Also I notice Ford uses an electronic rear locker on 4x2? Does this mean the rear is an open differential until its locked? I usually like a standard limited slip.

 

I have an 11 XLT SCREW with the Ecoboost and 3.15 open diff and 18" wheels. no need to worry about top speed on any of them becasue they are limited to just over 100 mph. As for tow and go... Mine will bark the tires with ease and traction control kicks in. If you do a bunch of stop and go driving in traffic I think a good rear would be the 3.55. If you are on the highway mostly you can't go wrong with the 3.15. jmo

 

I have the exact same configuration as you are looking at except I did the 3.55LSD. I"ve got a silver FX2 w/ the 20" wheels. I opted for that gear ratio because it is the middle of the road of what's available and it's limited slip and gets great mileage and has great manners for city driving as well.

 

I have the 3.55 in mine, no shortage of power down low. The 3.15 will be fine.

 

Welcome

 

Thanks for the reply's, I'm just going to go test drive it and see how it feels, sounds like it will be plenty strong if its not I'm just going to order a 3.55 truck.

 

I have the 3:15 in mine ---- i personally think it is awesome, but it would depend on what you are comparing it to i guess

--- my last 2 trucks were a F150 with 5.4L and 3.73, and a Chev 2500HD with a 4.11 and 6.0

--- The EB with 3.15 is quicker and faster than either of these by far, but i havent hooked a trailer up to it yet

 

Drive as many trucks as you can. I have the 3.73 and some are saying there is a noticable difference from 3.55 to 3.73. I would also say drive a 5.0 and see how you like that. I made a mistake by never driving the 5.0 or 6.2, wish I did. Still love the Ecoboost.