I own a 2016 F150 4x2 5.5' SCrew with the MaxTow package. (Yes, I'm sure it's Max.) It includes an electronic-locking rear differential.

What is the purpose of the e-locker? Is it a poor man's 4WD? Under what conditions is it advantageous? When should I not use it?

Thanks in advance for helpful replies.

 

Locks the differential so both rear axles are locked toether to result in increased traction on slick surfaces.

Sorta. I don't need 4WD to go on down the road after a light snow.

One rear wheel on a road surface with good traction but the other one on wet grass or mud and climbing a grade. With an open axle you're going to just spin the wheel with low traction, so you're stuck. With e-locker you can mash the button to lock the axles and then the tire with good traction can get you going again.

On dry pavement, or any road with good traction. When you make even a slight turn, the two rear tires need to travel at different speeds. The tire on the outside of the curve has to rotate faster to keep up with the tire on the inside of the curve. The differential is designed to allow that different speed of the two rear ties. With a locked differential, both tires have to turn at the same speed, so the tire on the outside of the curve drags around the curve instead of rolling around the curve. On a low traction road, such as a wet pavement, the tires can slide along without you noticing. But with a locked axle on dry pavement, the rear tire(s) will make a bump-bump-bump sound as they are dragged around the curve.

 

Anytime one tire spins, use it. If no tires spin, don't use it.

 

Do not use it on a turn with good traction. It'll growl and chirp the tires.

 

How does LS work different from e-locker?

 

An LS permits one wheel to turn faster than the other, say, when performing a U-turn; even when doing simple 90-degree left or right turns but transfer torque to both axles when driving in a straight line.

A locked differential is a bonus when driving off-highway and the truck's suspension is twisted travelling through a gulch, crossing a stream, etc... and there's a rear wheel hanging in the air momentarily.

With an open diff, the truck will cease any forward motion. Some Limited Slip diffs may not bail you out of that situation, either. It depends on the design of the unit. With a locker, however, the wheel that is on the ground will continue to transmit 100% driveline torque.

 

The replies above have covered when, but I wanted to remind you that the "Electronic" portion of the "Electronic Locking Differential" will switch off the locked action and return the differential to an "open" characteristic at speeds above +/- 20 MPH. The exact information will be found in your F150 Owners Manual.

 

When I am backing up my 3500 lb trailer up to its spot up a slight upgrade on my stone driveway, I lock the rear and both rear tires dig in and not spin. With it not locked, one tire may spin on the stones

 

Thanks for the education. The examples are particularly helpful.

 

An elocker or an LSD are not part of the 4WD equation, which has entirely to do with the transfer case. 4WD means power is made available to all four wheels, not that all four wheels will maintain forward momentum.

So, you can have a transfer case that provides power to both axles in either an open configuration (like a regular differential), a locked configuration, or an on demand configuration (like limited slip).

And then you can do the same on each axle.

Many serious 4-wheelers consider a locker the go-to component, far from a 'poor man's' component both in perception and cost. It may be a simple design, but it works really well, and it's more important to get the right tires for the surface.