Ever turn on 4-high while going 60mph?

Number of total wheels X Number of driven wheels

 

The only damage you will do running at that speed is when you are going around a corner on dry pavement. In a straight line you will be ok.

 

If you have to look for a place to "exercise" 4wd because you don't have any other need to use it. ....why'd you get it?

 

A lot of people will get the 4wd for extra traction in the Winter. In the summer months is when they need to "exercise" the 4wd.

 

Primarily for winter, The other 9 months is 2x4. Still need to exercise the 4x4 system though

 

Ah

 

OK, so to recap this riveting conversation that seems to come up once every so many years.

1. Yeah, you can be in 4x4 mode to lube up your system at highway speeds , preferably on straight roads or during poor traction conditions. There is OP's answer.
   
2. An open differential allows your wheels to travel at different speeds. It applies torque to both wheels, but more torque to the wheel with the least amount of traction (making one "think" that only one wheel is powered because that is what we see when we loose traction on one wheel) Otherwise power is going to both wheels.
   
3. A locked differential provides a mechanism to put 50% torque to both wheels at the same time (not good when turning in the dry) regardless of the traction available.
   
4. Toyota did use mechanical clutch based LSD differentials on TRD Sport models until 2009. I have one (2006) and I don't have TRAC. LSD means "limited slip" so that more torque is available to the wheel that has traction. By the way, my LSD works well enough that on quick turns during braking I can feel some wheel hop.
   
5. AWD vehicles, like Subies and even some Ferrari's have differentials (or some other torque management system) not only between the wheels, but also between the front and back axles. This means that the axles can rotate at different speeds (think a bump, hill, turn). Full time 4x4's have transfer cases which act as a locker between the front and back.
6. There are vehicles with 3 differentials, and 3 lockers. These can behave like AWD and full time 4x4. (Land Rover has examples)
7. * Bonus Answer TRAC and other computer simulated products use a combination of throttle and brake input to alter the traction available and hence the percentage of torque available. Something like dual turning brakes on a buggy, but controlled much faster by the computer.

 

Nope, wasn't at all especially at 4:30am when I first got into my truck.

 

The only time I would ever do this would be if I hit a large enough black ice patch or something similar that sent me into a sliding skid. This happened once on a 2 lane deserted highway. Hit the slippery patch on a shaded curve. Sent me heading to the opposite side guard rail. I pulled my transfer shift lever straight back('04)and it went right into 4hi. Saved my butt and some serious damage to my rig. Great truck! I would never do this just to get my monthly 10 in. I'd find a dirt road someplace. Much more fun that way anyhow.

 

I don't think you understand. We may not "need" it at 65-80 (highway speeds) but a FWD vehicle would be just fine on those slippery roads going that speed, whereas a RWD with a very lightweight rear end could try to slip here or there on a slippery patch. It's insurance, and safer than going that speed, which is just fine in those conditions, without. It's literally safer to drive my Honda Fit down the cold highway (FWD) than my truck in just RWD. Hope that makes sense to you. I put on well over 20,000 miles a year, most of which on the highway, and many of which on cold/icy highways. I've lost control of the rear end when in RWD. Never in 4WD, FWD or AWD.

RWD is literally the worst thing you can have on a slippery highway ha.

 

Actually that's part time 4WD. Which is what our trucks have. Full time 4WD has an open center differential much like AWD.

 

Thank you for the clarification and extended answers!!!

 

Shouldn't really be engaging while wheels are slipping though. Could cause damage

 

Right. Every single person who drives those highways year in and year out feels perfectly comfortable with going the posted speed, but I'll let them know to slow down because you said so haha.

RWD is the only option that isn't safe. Everything else is more than sufficient.

 

you'll never get through to them.
Many think having 4x4 or AWD make them invincible in poor weather conditions, that they do not need to slow down.

Doesn't matter what drive you have, if its slippery means you won't be able to stop the same, and no drive system will help stop you.

I see more 4x4s and AWD in the ditches in the winter months than I see FWD or RWD vehicles.

 

Is that why you have so many "X" marks the spot signs in your state? Because all those people felt perfectly comfortable?

I'll just quit wearing my seatbelt too. I feel perfectly comfortable.

Why can't I find the ICE setting on my multi-terrain select then?

 

Pulled five 19-year-olds out of a DCSB 4x4 Dakota doing 90 down I-135 two winters ago. Hit ice and then nailed a bridge embankment. My patient got off easy... he only snapped his femur in half. He should be walking again by now if everything went okay with the 5 surgeries.

But hey, what do I know.

 

used to be ignorant like that too until one of my friends got in a bad accident. Since then I've slowed down in shit conditions and am yet to be in a ditch again like I was in the past. Doesn't matter how good your tires are or your skill level. When it comes to snow covered roads and ice, just need to slow down.


When the conditions are bad like that you just have to slow down. Not worth killing yourself or someone else.
Nothing in life is worth rushing like that in bad conditions.


I've been in 4x4 and AWD vehicles in those conditions, when it comes to black ice patches neither guarantee you're going to keep traction and control.

 

Amen brother!

People need to slow down and be safe. Not just for themselves but for other drivers on the road and their passengers.

 

So very true. I live in Colorado and see if frequently as well, usually from people who have just moved here and don't understand how to drive in inclement weather. It seems they feel the added grip of all four wheels on acceleration, but don't realize it doesn't make a difference on deceleration; all cars have four wheel braking. Tires are what make the biggest difference, and sadly, most people don't seem to believe that or just don't care.