What's the point of an open diff with AWD?

[1998Exp]

I know that this has been discussed before, but couldn't see any resolution.
In my quest to find a 'decent' 2nd gen for an offspring, I came across a good-looking XLT with V8/AWD drivetrain. To my surprise, the axle code was 45 = 3.55 ratio, open differential. Looks like for the XLT open diff was standard, unless someone paid extra for a limiited slip, and only the EB and Limited got LSD.
Far from being an expert on four-wheeling, but what's the point of having an AWD with on open rear diff? The front one on those vehicles is always open, so if the rear is open too you can have two wheels spinning, one on each axle, and the vehicle going nowhere. Am I missing something?

 

[pbnj22]

im interested to hear the answer too.. seams like it kinda defeats the purpose of AWD to have an open front and rear diff. i have a 00 5.0 xlt AWD (not sure what rear end) but the thing is a beast in the snow and icy crap that i get up here in northern minnesota even with mediocre all season radials.. ive worked at a dealership and drove hundreds of cars and my explorer is one of the best i have driven as far as traction in the snow..

 

[R1dd1cK]

Interesting. My wifes 98 XLT is the V8 AWD and its axle code is D2 or D4. So it came with limited slip.

 

[FLOffroad]

AWD with dual opens is what most Subarus have - it's not really for serious offroading. There are videos of people with Subarus demonstrating the fault of F&R opens with AWD.

Anyway, the center diff on an AWD is often biased front or rear, but the spilt usually ranges between 70-30 and 30-70 (front-rear). When your average person encounters low traction on the road it's not a massive field of 0 traction, rather patchy spots. So, from the manufacturer's perspective, the front/rear split usually allows one axle to find some grip, which is enough to pull the vehicle along.

Essentially, AWD with opens is not really for offroad, it's for "all-weather."

 

[pbnj22]

And I would assume it gets slightly better gas mileage? Since your essentially pushing power to the tire with least resistance rather than the one with most? Not that the difference would be very neglible

 

[SoNic67]

That's useful just for Ford saving money on their "AWD" lower priced models.
If you have paid already for AWD, the difference to a LS on rear is so small is not even funny. There is no difference in mileage, unless you turn left-right at every 50 feet (that's when LS uses slightly mode power).

Marketing ploy. In today's market, probably $100 lower selling price can make a difference in 1000 more vehicles sold to buyers that don't know all the details...

 

[Cranmaro99]

I have an AWD 5.0 Explorer; 2001 Limited. It has 3.73 gear ratios and a limited slip rear end. Perfect!