HI all,

First post on the forum but have been lurking for quite a while. I'm getting ready to order a 2016 lariat SC 4X4. I've research the heck out of the truck and fell in love with it when Ford invited me to a private test drive a year ago. I drove the 2.7 which I want in 4x4 and couldn't believe it. I was sold but have been waiting for the 16's. My question is, should I get a locking 3.55 rear end or not? I understand that a locker allows both rear wheels to have equal power but am wondering how much I need it? I only do light off road and boat launch ramps. If someone can explain it a litter better to me I would appreciate it. I don't want to make a wrong choice.

Thanks!

 

It is very useful. Particularly on boat ramps. Get it.

 

It is better to have it and not need it than to need it and not have it.
No 4x4 should be without one.

 

Since you're getting a 4x4 it sounds to me like you don't really need it, but for a few hundred dollars, why not? It was a must have for me because I'll be plowing snow and I've been stuck too many times with my old plow truck with only one back tire spinning.

 

locking cant be locked over X mph. limited slip works at all mph. So at 40 on a slick road nothing is locked. Some will say that's good some will say that's bad and there are many complaint of it auto unlocking over X mph. So in my mind figure where you want the extra traction - slow speed from a dig ONLY but a true locker or limited slip at all speeds.

 

The problem you have in certain situations is 4x4 should not be used on dry pavement. Places like boat ramps you can start with the rear wheels wet then all of the sudden you are on dry pavement making turns and binding up the 4WD and dragging tires because one tire needs to move faster than the system will allow. 4WD is not AWD. With an electronically locking differential it senses when a tire is spinning and applies power to the proper place. Although this latest 4x4 system is a lot smarter than prior generations so rather than just locking everything up it might do things a bit smarter.

 

Better looking at it, than looking for it. For the price, the piece of mind that its there if you need it is worth it.

 

The locking differential does NOT work as you described. Pull the button, it locks. Push the button back in, it unlocks.

As far as using 4x4 on a boat ramp, I would turn it on AND pull the ELD. After I got a few feet up the ramp, safely off anything that might cause me to slip, I would push in the ELD and then turn off 4x4, and then keep driving. Both take seconds.

I have it, and it's great for pulling out at a stop sign, deep in snow, to cross a major road. 4x4 is good, but the ELD makes it better.

I found this video quite helpful:

 

I have a similar Lariat Scab 4x4 on order.
Yes, get the elocker differential; it's more fun in mud.
And I think the 2.7 engine is not available in Scab 4x4. You'll have to pick a bigger one...

 

I have the locking differential on my truck and it definitely walks the rear end tires. I can show you on dry pavement rubber marks going back and forth. Remove traction control and both tires lock. I have not dug into it in detail yet so I'll reserve further comment but there is interaction with traction control on this system. I fully admit I have not taken the time yet to completely understand the system but some playing around with the system tells me it does not just fully lock up the rear end.