OK I have a 05 Sport V8. Be easy on me now, I do know what a diff loc is and when you should use it, However, What Is the center Diff loc? And when should I use it? Any time I am in 4Lo? Thanks



HDHP

Center diff lock is different from front/rear in the sense that it ties the front and rear axles together, splitting the power that way. It basically makes it 4WD as opposed to AWD. I only use it when I off-road.

This is why when you hear the term "triple locked" they mean front, rear, and center.

Ahh, OK Makes sense!
Going to be in some snow this weekend so I should use the center diff lock.
Let me ask you this...
Do I need to put it in 4Lo before I push the center diff loc?

Thanks Again!


HDHP

No, you don't need to be in low range to use it. The center diff lock works independent of 4lo/4hi. I would say to just avoid highway speeds with it locked, at that point it's not helping you anyway so why bother.

if youre just doing normal driving on snowy roads... you do not want or need the center diff locked. thats more for extreme conditions like if you go off the road & are stuck in a ditch, or for actual off roading where you need the most traction possible. for "normal" snowy roads just use 4hi.

4lo has a very limited speed range, usually for low speed off roading, dont use it to drive around on.

the owners manual has a pretty good explanation of when center diff lock is needed.

Center diff lock engaged locks the front and rear axle rotation 1:1, similar to how a rear diff lock would work.

Unlocked, it allows slip between the front rear, which functions no different than most AWD cars on the road like an Audi.

For snow driving, unlocked is best. Having tried both, unlocked breaks traction much less than you would if you were locked while turning because it allows slip, preventing the tires from scrubbing like it would on high traction surfaces.

It’s a feature that makes these trucks very versatile in all conditions and all terrains. I like it a lot.

You can run unlocked/locked high or low, which is also really cool.

Is it true that locking the center also shuts off some of the safety features that would be helpful in the snow? Traction control and anti-skid maybe? I thought I read that somewhere. I know 4 low locked makes the VSC & TRAC lights come on, may be true for locked in both modes. I forget as it's been awhile since I locked it. I also recall that you have to set 4wd high, then lock then put it in 4wd low or it will beep at you.

i think it disables all that in both modes when locked. not 100% sure

Locking the center disables VSC which is appropriate for off-road driving. IIRC, I am pretty sure this behavior is the same in 4H or 4L.

This is another reason not to lock in the snow in normal driving conditions. You don’t want to give it more chances to break traction, and you want VSC on.

Locking the center is really discretionary, the user should know when it’s appropriate as there is not always a hard & fast rule similar to locking the rear differential. Just as an example, locking the rear in snow on public roads is either going to make for some very fun and dangerous driving conditions as it won’t take much to kick the rear end out on turns. Locking the center will promote scrubbing between the front and rear axles, which will provide more opportunity to break traction.

That’s not to say there isn’t an appropriate time to lock in the snow, because there is.

One thing to add is that engaging the center diff while on a high traction surface (pavement) can put stress on the drivetrain as the front and rear axles can no longer rotate independently. In snow I typically engage it during situations where I want to turn off traction control like deep snow on FS roads or 2tracks, or when I am trying to get unstuck. Stays unlocked for pretty much every other winter driving situation.

Exactly how I was understanding it but wanted to clarify for myself and the OP.