Hi Everyone
Being "old school", we wanted a limited slip differential. the Electronic Locking Axle is what we are ending up with. How is this different from LSD, if at all? At times having both rear wheels turning (in particular in a turn) is a necessity for us. We live on an incline on 5 acres and we have been stuck more than once. I have searched this form and I can't seem to find and exact definition here or on the Ford website. And reading all the "searches" on this topic was more than a little confusing.
Regards (and thanks)
Bill

 

 

Limited Slip, when one wheel spins, it sends power to the other side (When it works). Locking, is an open diff, and sends power to the wheel that is easier to spin, when activated, it locks the rear wheels together. Turns with it locked are a bad idea, somethings got to give, and if your lucky, its wheel hop (Breaking traction) The E locker diactivates at 20MPH

 

 

Thanks for your explanations.
How is it turned on? when my current truck (a Silverado 2500 4x4) is in 4wd I can feel the outside wheel spin in a turn. Not happy about it but when you need it, you need it, turns or no turns. We have lots of oaks and getting between them can be interesting in winter.
Regards
Bill

 

First, both are regarded as "traction differentials" but there are significant engineering differences between the two.

With a limited slip, the axles spline into side gears in the differential. Between the differential case and the side gears are clutch packs. There are also spider gears in the differential case just as in an open differential. There is also a pre-load spring set pressing the side gears and lightly compressing the clutch packs. A limited slip is a completely passive differential, meaning it works without your intervention. They way it works is when torque is applied to the axles, the spider gears push the side gears into the clutch pack and this compression causes the clutch pack to lock up. An open differential does the same thing, but there is a thrust washer between the side gear and the case, instead of a clutch pack. The higher the torque load, the more compressive force you apply to the clutch packs. When you enter a turn at modest throttle settings, the input force from the outside wheel causes the clutch pack to slip allowing differential action to occur. A limited slip can still do a one-tire spin. This occurs where you have one tire on ice, the other on dry pavement. The input torque is too low for the axles to "lockup" so one tire spins on the ice (or mud, or whatever). To get traction on both tires, you have to lightly apply the parking brake. This resistance raises the input torque which allows the spider gears to press harder on the side gears.

A locker is very different. The difference you are interested in is that when locked, the axles are tied together and there is no torque biasing between the axles and they turn at the same speed. When locked, the is no differential action. They do this by eliminating the meshed spider and side gears with a dog-toothed clutches. With the Ford E-Locker, you select the lock and at speeds below 20mph, the axles are locked together. Above 20mph, the axles automatically unlock. On dry pavement, locking the axles can cause a tire to skip since it can't rotate at the same speed. On slippery surface, both tires are going to drive regardless of steering. When unlocked, the differential behave just like an open differential, meaning it has good, safe street manners. An automatic locker, which is different still from the E-Locker, and is not used in the SD, but is worth mentioning since some folks mix up the two. An automatic locker is always locked until you enter a turn at modest throttle settings that overrun one of the dog clutches, causing it to release. An automatic locker has some quirky street manners that you have to be aware of but it's of no consequence to you since that's not what is available to you.

If you want to graphically see the differences, you can search the Internet for the diagrams for each. The diagrams don't explain how they work, but you know that now and can reach your "Ah ha" moment.

Some folks prefer a limited slip, some the locker and some get by just fine with an open differential.

 

 

Whwn we activate 4x4, should we engage the locker as well by pulling the **** out too?

 

I've had the e-locker and limited slip. I feel the limited slip is quite a bit more versatile. Using the e-locker in the snow on pavement created a hopping condition where the rear tried to move to the side. This was not in a turn, but in a straight line. It did work very well in the snow on our quarter mile long sloped and curving driveway at low speed. Have not seen the 2 wheel drive vehicle that can make it up our driveway in snow yet.
The limited slip works very well also, but with less fuss. No need to activate it, it's there when you need it.
In mud, pulling a camper out of a field, I much prefer the locker. In snow on any kind of pavement, I prefer the limited slip. A shame we can't have both in one vehicle.

 

For my use the limited slip is useless as a teats on a boar hog. The real lock up is just awesome. For the mall crawler limited slip would be the best by far.

 

link: look at this it will tell how it works

 

 

This is completely wrong. There is NO torque biasing with a locker...Detroit Locker, E-Locker, Air Locker, makes no difference. When the locker is engaged, the axles are locked together as if it was a spool. A limited slip allows torque biasing between the axles, meaning they can turn independent of one another.

 

 

When I'm driving on slippery roads ( snow ) or muddy dirt trails and making turns - I just use 4wd. If I'm going in a straight line, and need maximum traction, then lock the axle.