I'm sure the HL/H/N/L is similar to the Series transfer case. You can have it in high range, and high range locked (by pushing down the yellow **** in a Series), but move it to low and it's in locked 4WD (and on the Series the yellow **** pops back up).

 

The idea that High requires manual locking, but Low locks the center diff sounds sensible to me.

Happily, *I* have this new thing y'all haven't heard about called The Google. and it leads me here, which confirms the theory.

:-)

 

yes i know what google is . but im on such sh!tty internet here that a goole search isnt feasable - the other day i waited 13 HOURS! for my yahoo mail to load. thats why i turned to my local SMEs (subject matter experts) on all things 4x4 - you guys.

im writing this from some poop-hole FOB (foward operating base) in northern iraq.

and thank you for the info. i now know what high lock is but what is a situation in which one would use it? i guess i dont understand what advantage it would have over normal all wheel drive mode?

thanks guys

 

I cant get ahold of my cousin.

Pilsner-the HUMVEE is like our Rovers, it is NOT all wheel drive. It is FULL TIME FOUR WHEEL DRIVE, HUGE difference.
The advantage of locking the center diff while in hi range would be for just like I said, driving at hi speed on loose/soft surfaces.
Like driving 180 miles in a blizzard or high tailing it across a desert for 2 examples.

 

I'm pretty sure someone said that the HUMVEE's center differential is always locked in low range. Oh yeah, that was me. I got the information from a light wheeled vehicle mechanic in the Army. Who needs google when I can go to someone that knows the vehicles inside and out.

 

Sadly most of the mechanics i know around here are experts on strykers and know almost nothing about humvees. which makes sense considering we have a 100+ strykers and about 15 humvees.
but the loose sand/snow thing makes sense. i will pass the info along to my driving student.

again, the brain trust saves the day.