My first vehicle with 4wd. We have snow & ice on the street … about 2” of snow, and as it melts then freezes we have a little ice. Can i use 4H continuously without damaging the truck? I think once i get out of the neighborhood the streets will be mostly clear, so it would only be a mile or two.

 

You can use 4wd high on dry roads if you know how to. To answer your question. Run in 4wd high take wide slow turns, if you feel the front binding one of two things is going on. One roads are to dry, tow you are turning to sharp. If the streets out of your neighborhood are clear turn off 4wd. If not leave it on. I say go to a parking lot that has been halfway cleaned and play a bit, you will figure it out pretty quick.

 

Thanks. Locking the diff is the real problem, right? Don’t want to do that in this situation.

 

As long as enough pavement is covered, so the wheels can slip a bit while turning, you can use 4WH. Same with locking the read diff.

 

The manual explains 4wd rather well


https://www.fordservicecontent.com/F...US.pdf#page277

 

If you are sitting at a stop light with ice or a slick surface, you can use the losking diff. Just turn it off and DON"T turn with it on. If you forget to turn it of for some reason it turns itself off above 20MPH I think and will come back on under 20MPH. Again the biggest thing the rear diff is helpful for is climbing a slick hill (boat ramp), taken off from an icy spot (stop sign/ stop light). If you are working in a muddy field or your lawn and don't want to tear up the lawn. As I said go to the mall parking lot and play with each one, when I buy a new truck I take my wife out to an empty snow covered parking lot, and let her play with the truck. She ends up turning off TC and 4wd and tries to spin it. That way she will know how to handle it on the roads.

 

If your truck has 4A, then absolutely. If you only have 4H, then I personally would not drive/turn on dry pavement or above moderate speeds in 4H.

4A is essentially the same as AWD, which is designed to be engaged all the time. Think: All the cars and SUVs with full-time AWD.

4H is essentially 4WD and is not DESIGNED to be engaged all the time. When engaged, your front and rear axles are spinning at the same speed -- not good, especially when turning. It will also lead to faster wear and risk of damage to various components of the system itself as well as suspension parts.

 

Assuming you pull up straight to the stop sign leaving the neighborhood, I would just click it into 2wd when taking off from there.

You said 2 inches of snow and ice before that and that would be what its designed for.

 

If you do 2 things you will likely never have issues with the 4X4 system.

#1 Use it or lose it.

You need to engage 4X4 and use it regularly even if it's only for a mile or 2. About 10 miles/month is recommended but nobody said it had to all be at the same time. I need to drive a couple of miles on a gravel road several times most months. I flip the switch to 4hi every time. Any other time I find myself on a dirt/gravel road I get in a few miles in 4X4. I don't shift to 4lo as often, but if I'm not in a hurry will do so even if for only a few hundred yards.

Doing this will keep everything lubricated and it will make the shift when needed. If you don't use 4X4 for months or years the internals don't get lubed and won't move to engage when needed. Even electrical connections need to be switched on/off regularly to ensure they work.

#2 Use 4X4 as little as possible when traction is good..

This includes wet pavement. A lot of modern vehicles have "All wheel Drive" and many novices don't understand true 4X4. When you drive around a corner each of the 4 wheels needs to move at different speeds because they are traveling different distances to arrive at the same spot. When moving forward the inside front wheel has the least distance and is turning a lot slower than the outside rear wheel which has to move much faster.

In 2WD this isn't an issue. But in 4X4 the transmission and transfer case want all 4 wheels to turn at the same speed. The inside front MUST slip and spin slightly when cornering. If on loose or slippery surfaces this doesn't hurt anything. If traction is good it puts the entire drive train in a bind.

It's possible, but rare for something to simply break when you do this. You can get away with it for short periods and there are times when it may be necessary. There will be times when you forget to disengage 4X4 when you get back to pavement. But I'd advise doing so as little as possible. The more you do it, the sooner you're going to have to start replacing 4X4 components.

AWD uses computers and wheel speed sensors to send power to all 4 wheels yet let them turn at different speeds. AWD is a newer more complex system that is actually much better for snow covered and wet roads with no downsides on dry pavement. True 4X4 is much better in really harsh off road situations.

4X4 can be used on snow covered roads but I only use it as needed. If the pavement is completely covered with snow/ice use it. If I'm in an area with patchy coverage with clear pavement and other snowy areas I switch back and forth as necessary.

I've been driving 4X4 for 50 years now. When I was younger, I made the mistake of not using it regularly and had issues with it not engaging when needed. I also had a 1975 Jeep truck that used vacuum hoses to engage 4X4. Somehow the hoses got reversed and even though I had the switch in the 2wd position I was in 4X4. I wasn't experienced enough to recognize the problem until the transfer case needed to be rebuilt. And it didn't take many miles.

Right. The locking diff will get you in trouble. MOST newer vehicles have some sort of traction control that does better on snow/ice than locking the diff. But if you don't have traction control you could lock the diff just long enough to get moving from a stop. Turn it off as soon as you're moving.

 

From whom?