https://owner.ford.com/content/ford-...vt-raptor.html

Same type of switch for normal 4x4 (with the locker option), just no off-road selector switch.

Edit: press the close button for "vehicle selection" in the link (above the video) to view it.

 

All good winter tires have ALOT of siping.

 

4A (4auto) is not the same as an AWD system.

 

I have thought about this too; adding weight does two things, moves the center of gravity so the rear tires have more weight on them, and increases the total weight. It's a trade-off between traction and stopping (traction is directly related to friction [f], which is related to weight [N]: [f=uN])

So here is an explanation with math and science! (I think you nerd sniped me...https://www.xkcd.com/356/)

Lets assume a 2015 Ford F-150 Lariat 4dr SuperCrew 4WD 5.5 ft. SB (5.0L 8cyl 6A) simply because Edmunds has lots of numbers for it: https://www.edmunds.com/ford/f-150/2...st-specs1.html

The weight distribution is 58.7% front, and 5233 pounds total. So that works out to 3071 Lbs front and 2161 Lbs rear. It will take 909 Pounds to perfectly center the weight distribution. This will increase the total weight to 6142 pounds, that is a lot of weight to try to stop or change direction (you know momentum = weight x speed).

If we now assume that the added weight placed against the tailgate is 1 foot behind the axle, I can make the following free body diagram (an engineering technique to show forces and balance)




In order to get the weight distribution equal, the moments (force times distance to CG) on the front and back of the truck have to equal. This truck has a 157 inch wheelbase (it's actually 145", but the top of the website said 6.6' WB in one spot and I already ran all the math) so:

(Front axle x 157/2) + (Total weight x (.587 x 157)-(157/2)) = (Rear axle x 157/2) + (Added weight x (157/2 +12))

The front and rear weights are equal so they drop out, leaving: (Total weight x ((.587 x 157)-(157/2)) = (Added weight x (157/2 +12))

The math works out to an added weight of 790 pounds.

That's 790 pounds against the tailgate vs 909 pounds over the axle to make the center of gravity in the middle of that truck, that's also 119 less pounds to stop.

Now, I don't know anyone who adds 500+ pounds of weight to the truck to drive it in the snow, but by saying adding the weight to the tailgate makes a pendulum effect is just wrong. First, you are not adding enough weight to make the rear heavier than the front, and second, if the goal is to add more weight to the rear axle for increased friction/traction, placing the load further back gets you the biggest benefit with less overall weight added, which will make it easier to stop.

For example, I found adding 450 pounds made my truck stop with an extra 12 feet at 40 MPH in whatever type of snow I was running my tests. If you can keep the weight down, you will stop faster.

 

You don't know me, but I add about 550 lbs of sandbags over the rear axle of my F-250 for winter traction. I have a wooden frame I put them in and strap it in place.

As far as weight behind the axle, been there, done that. And I won't do it again. A little weight is ok, but the more weight you add behind the rear axle, the easier it will cause the rear end to spin around on you if you start to fishtail. Think of it as a lever. The more weight behind the fulcrum point (rear axle), the stronger the force on the lever. More leverage working against you = easier to lose control.

 

it locks the rear differential so that both rear wheels turn at the same time.

 

Seems to be a lot of misinformation and generalization about tire sizes for snow, especially with regard to contact area. What you want or need as far as contact area depends upon driving conditions.

If you're driving in an area that gets very dry (loose) snow, then yes, you may want a narrow tire to cut through the snow and let the tires contact the road/ground better. If you're driving on hardpacked snow, then you need more grip from your tires, which means more contact area (wider is better). A good snow tire with lots of siping makes a good compromise.

 

You are kind of splitting hairs but fine. The F150 has a transfer case, the system still acts like AWD.

4A (4x4 AUTO)* provides electronic
control four-wheel drive with power
delivered to the front and rear wheels,
as required, for increased traction. This
is appropriate for all on-road driving
conditions, including dry road surfaces,
but is especially useful on wet
pavement, snow, dirt or gravel.

 

Why are the Hankook ATM's bad?

I've got them as OEM on my 17 and this truck is sad in 2WD, lockers or not. To look at them the tread seems adequate. Yet,this truck (with those tires) performs the worst of any I've yet owned. I thought, perhaps, it's because this truck is lighter than my others?

Because the bed is so small I want to avoid putting weight in the back, (I know it would help) but space is already limited. Back in the day when everyone had an 8 foot bed there was still plenty of bed space after the sandbags. That's no longer the case.

So, is it really just the tires or that the truck is too light?

BTW; my last truck was a 2013 FX4 and did much better once the roads became slick.

 

It's so interesting to read these opinions, my feeling is exactly the opposite. I think they are the best OEM tire Ford has put on any truck I have purchased. Shrug
I should note I have a 6.5ft bed with a cap.