Keep in mind that if you drive any faster than 20 mph and the locker disengages.

 

Just to clarify...the gearing (3.31s) is independent of the differential (open, LS, locker).

For driving on the street in the snow, a locked rear isn't what you want. If you get an e-locker, it will be an open diff until to switch it on. When on, it's effectively a spool with both rear tires 100% locked together. On snowy/icey roads, this cause the rear axle to slide around (fish tail) much quicker than an open diff.

 

this is only true if both rear tires hit the ice. if only one does, that's when you want a locked diff IMO.

As for the traction control....I wouldn't count on it doing much. 4x4 should be good.

 

If your getting a 4wd, then the locker will hardly, to never, be needed. If 2wd things change. The Ecoboost has such a early delivery of torque it's difficult to not spin in marginal conditions. The e-locker is quiet, simple to engage, and effective. Automatically dis-engages and re-engages depending on speed, I never notice the change except for traction. It does lock the rear firmly and will be very noticeable in slow turns, skipping and hopping hard on dry pavement. I live in WI, across the pond, and drive 2wd XL, using the locker often just to start rolling. KM

 

True. I was thinking more along the lines of the road being completely covered in snow or ice...Around here when we do get snow (usually once or twice a year), the DOT is kind enough to scrape all the sticky, good traction snow off the road and leave on the frozen/icey stuff for us to drive on.

 

I previously owned a '14 with open diff. Reading up on the electonic 'lsd' info from Ford I was hopeful it would work. My experience with it was not good. On a wet soccer field my wife's 2x4 with mechanical LSD walked off with no problem. I was left doing a one wheel spin and had to engage 4x4. Before anyone asks, I was not flooring it. Just simply could not get the electronics to do their thing. Tried it with the TCS button on and off. Said screw it and engaged 4L to leave. Wife of course reminded me of that all the time.

Needless to say my new '18 has FX4 with electronic locker. Somewhat wish it was mechanical like my wife's so as to be working all the time. I've not had a chance to try it out yet. My truck is only a week old.

 

Right, the 'traction control' is not to be relied upon. It is not electronic power delivery to axles, and isn't going to act like a locking or limited slip differential. These trucks do not have the type of technology range rovers have. (though if they did, what would an F150 cost? $110k? LOL)

 

The auto AWD option on the limited is actually much better than I expected it to be. I can run that in the snowy road conditions just about anywhere and it responds quickly where slippage occurs. Mine also comes with the locking differential by just pulling the **** out but I have yet to need it in any conditions presented to me so far. We don't get snow in KS like you do up north but christ if I needed to lock the diff to be driving on the roads I probably wouldn't be leaving the house.

 

I wouldn't touch a 5.0 with 3.31 gears with the older 6 speed transmission. Not enough power. In fact if you compare the 3.5 EB with 3.31 gears to the 5.0 with 3.55's they are a virtual tie in power. The new 10 speed should offset the difference in gearing, at least in theory. But I'm still skeptical. If anything I tend to err on the side of having gears lower than needed rather than getting stuck with a vehicle without enough power. On paper Ford can show 1 mpg better fuel mileage and that helps them meet CAFE standards. In the real world you won't save any gas with a 3.31 over a 3.55 or even a 3.73.

An E-locker helps if in a situation where one rear wheel is on solid ground and the other is not. They are great to get you moving under those conditions. But once underway they are a handicap rather than help.