4H/4WD Wet Pavement Dilemma

[HenryMac]

I wouldn't be concerned as long as you aren't hearing or feeling anything abnormal while driving the truck.

We use 4H frequently because the roads here have patchy ice / packed snow. I turn the knob and change from 2H to 4H maybe 20 times in an hour. This is on fairly straight roads. And if in doubt as to if the road is slick, I use 4H, the exception however is that I always turn off 4H when making a 90 degree turn, like at stop signs, road intersections, etc.

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[jss81258]

According to the truck's manual, which I advise you thumb through, 4wd (4HI/LO) is not to be used on pavement (snow/ice covered is ok to use).

The jerking you are feeling is both front tires trying to rotate (spin) at the same speed. As the outside wheel has to travel a further distance, it must spin faster than the inside wheel that must travel a shorter distance. This forces one of the wheels (often the inside wheels) to rotate at teh same rate as the other wheel (outside). This binding-then-releasing-then-binding is the jerking you are feeling, and is the reason that 4wd is not supposed to be used on pavement. With a layer of snow, dirt, mud, what have you, the slipperiness of the surface allows the inside tire to rotate more smoothly. It would still be noticeable, however.

When you shifted the truck back to 2wd, it takes some time, effort, and/or distance traveled to unlock and disable the front end from receiving power. This is why you got the jerking feeling when in 2wd. When you shift to or from 4wd, you do not have it as soon as you flip the switch. The system is mechanical and things, like gears, must line up before they can engage, and must have "slack" in them before they can disengage. Think of a deadbolt in a door. If you're pulling on the door while it's locked shut it is very difficult to slide the deadbolt open.

As for the smell, tell your wife to take a shower. KIDDING! Ultimately, it was probably in her head. We humans love to see/smell/hear things when we think things are going wrong.

I would love to link you to the page with the info about 4wd, but my internet is far too slow. Hopefully someone else can help you.

>Edit: Go to youtube and type "4wd jerking". Lots of videos.

Actually, the inside tire and outside tire on either axle are free to rotate at different speeds due to the differential. Well, unless you have an elock and lock the rear differential. The jerking is due to the front axle being locked to the rear axle by the transfer case. In a turn, the radius is different between the front axle and rear axle.

 

[DT444T]

Actually, the inside tire and outside tire on either axle are free to rotate at different speeds due to the differential. Well, unless you have an elock and lock the rear differential. The jerking is due to the front axle being locked to the rear axle by the transfer case. In a turn, the radius is different between the front axle and rear axle.

Hurr I'm a durr.

You're absolutely correct.

 

[TXRanger13]

Thanks everyone. Now I just need to find some where to actually go off road and test out the 4WD system for real.

 

[jss81258]

Thanks everyone. Now I just need to find some where to actually go off road and test out the 4WD system for real.

Didn't you guys just get some snow up there? I wouldn't think finding a place to test would be all that hard.

I doubt you did any damage. I've driven short distances on dry pavement in 4wd with other vehicles for one reason or another without any problems. I wouldn't think the Ranger would be much different. I just wouldn't make a habit of it.

 

[Fawnbuster]

I will only add this-

Agreed

I concur with all the others. I will only add that just remember any four wheel or all wheel drive vehicles can accelerate quicker/faster/
easier than 2wd vehicles however they cannot stop faster in slick.conditions. over the course of my 34 years of law enforcement
I dreaded working the 1st and 2nd snows of the season, it always involved a lot of vehicles that had drivera new to operating all or 4 wheel drive vehicles. After a few times of driving them, they learned how to negotiate the roads once again.

Might also add that after a dry spell mist or gentle rain/snow is much worse to drive on as opposed to a hard rain that rinses the goo off the roads. As winter progresses watch out for the patches of sand that accumulate in intersections due to sand dropped by dot, if you have to maneuver as you hit the sand you lose traction

 

[Tito]

No harm harm done from what I read. I occasionally use 4h while its actively raining heavy; straight line only. I’ve grown to like the snow/sand gravel setting if you have the option. It’s the first option in the terrain options. When disengaging 4H, it takes a few feet to undo itself. Best to let off the gas and not be turning to let it engage without issue. If you’re in a highly populated county, drive out to a smaller county and find a county road to drive on. They are almost always dirt, gravel or caliche.