4WD on Pavement Questions

I am new to 4WD systems. I have had various cars with AWD, but never a 4WD system. From what I understand on the Tacoma there is no center differential, only a transfer case. Because of this the front and rear wheels are locked at the same speed, so there will be wheel slippage going around corners.

How should I drive the truck this winter, say when the roads are mixed with ice, snow and dry patches? Is it safe (non damaging) to make a 90 degree turn in 4WD if the road is dry? Frequently in New Hampshire we have rods that go from snow, to ice, to dry depending on plowing, traffic and sunlight on the road. It would be nice just to leave it in 4wd on days when it is mostly snow and ice, but this seems like a bad idea. I am tempted to just treat it like a 2wd car and put it into 4wd when off road, or on really snowy days.

According to Toyota we can drive the truck up to 55mph in 4WD mode. Realistically is this only on the highway where it is mostly straight line driving?

Also, why doesn't Toyota add a differential, with locker, in front of the transfer case? Seems like a simple thing to do to give you more flexibility. I would have paid a $1000 more for that.

 

Yes - tacomas have a transfer case, not a center differential.

The front & rear wheels are totally independant of eachother in 2WD. In 4WD, the power is sent to both front & rear wheels at the same rate and DO NOT have the ability to differentiate between them (if that makes sense). Because of this - driving in 4WD on dry pavement is not a good idea because there may be situations where the front & rear shaft speeds can be different and this can cause binding in the transfer case. Worse case scenario - you can cause damage to the transfer case.

DO NOT make tight turns while in 4WD. This puts a lot of pressure on your CV joints at the front axle shafts. You can turn - just be very cautious how hard you turn. If you're turning too tightly - you will notice the vehicle may start to buck....and it won'twant to move.

Long story short..... Feel free to use 4WD in any snowy, icy, or any slippy situations. Just be aware of the roadways - dry areas - etc. You want to stay stright on dry surfaces (pavement).

In the summer when it's raining pretty hard - I'll run 4WD on the highway up at 65mph. This is primarily to keep the 4WD setup lubricated regularly.

The Toyota 4Runner has a fulltime 4wd system with a center differential and will run 4WD all the time. The center differential is what 'differentiat's' the differences in speed front to back. These systems don't have a transfer case and don't have low range either. Jeep Grand Cherokee's also have a fulltime 4WD system and they have lo-range also. These systems have special center differentials/transfer cases that have 'slipping' capabilities to differentiate between front/rear speed differences and also allow power to go to certain wheels (front/back). These systems are very expensive and probably why they only make them for the more expensive SUV's.

Heck.....Toyota has to work on getting power seats in the tacoma before they put an extreme 4WD system in them!!

 

I also live in a area where the road go from sloppy to dry. The previous thread was dead on, but with a new truck as yours, just turn off the 4wd when coming into the dry areas, back on when the roads are slippery, you can "shift on the fly" at highway speeds, 55mph and lower. It would not be prudent to be going 55mph, engage the 4wd, then enter an area that is sloppy or slippery. Just because you can doesn't mean you should. 4wds go alot of places, and perform very well in crappy conditions, but don't stop any better. Forgive me if this seems elementary, but I see knuckleheads blow by me everyday during inclement conditions, and then down the road I see them in the ditch or all banged up with someone else with this look of WTF ? A little common sense goes a long way. Congrats with your truck, take some time to feel out the handling characteristics. At first good snow find a open parking lot and go from 4wd to non-4wd, a couple brake checks and hard turns should give some indications. Drive on.

 

Thanks for the replies. When it snowed last week I drove the truck as concrete jedi described, switching the system on and off. However I was just testing out the handling. And certainly not going very fast. Not that I ever go fast in the snow and ice - I am fully aware that it is the brakes and tires that are important for stopping and 4wd doesn't help at all in this regard.

 

Take it to an abandon & snowy parking lot - put it in 4WD and play around a bit. You'll be able to learn how the truck handles without actually being around any traffic. Just make sure there are no light poles to hit.

Try it in 2WD (in the snow) in the parking lot.... and you'll learn just how much you'll want/need 4WD.

 

I'd have to agree with jedi, shift on the fly when necessary.

 

It was actually raining pretty badly this morning and I decided to go ahead and try activating the 4wd for the first time. Not that I needed it, but just for kicks and giggles. I picked a part of the road that was straight. Rain was coming down pretty hard. I put it in 4WD for about 2 miles straight line. Just for lubrication purposes, it worked like a charm. Extremely easy to engage and disengage.

 

Not a bad idea to do that from time to time, maybe find a field or something a little sloppy, I should take some of my own advice...DOH !

 

I only got to enjoy seeing someone fly by me and land in the ditch just once...right before they went into a spin I was thinking .. maybe its not so slick... yep its slick!

 

i would like to drive in the snow

 

I can't wait for the snow.....it's fun.

 

Just tonight on my way home from work some punk flew by me on a double yellow line, it was raining like hell so I was at speed limit which was 35mph. About 5 minutes later I see him pointed south in the northbound lane, I slowed down to see if he was O.K. and to rub his nose in it , but as I slowed down he screwed down the road in the wrong direction, I called johnny law but they did not seem to care. I just hope he doesn't hurt or kill someone.

 

I experienced a seemingly extra-large amount of ASSBAGS on the roads this evening.

 

LL7, I live way out in the country and travel on miles and miles of dirt roads. Since, its country the roads are not salted because they pollute the lakes and wells so the roads turn to sheets of glass. I seldom use 4WD unless I'm going up or down hill. Those who have the TRD Sport will tell you how bad the original tires are. As long as you dont step on the gas or brakes aggressively, you should be OK and definitely don't make fast turns or the back end will come around. Once I tried to avoid hitting a deer and ended up in a ditch (both driver side wheels) while on 2WD. The wheels spun on 2WD and 4WD would not engage. That was a bummer. When the truck was new, the 4WD would not engage without moving the truck forward/back a couple of times. That seems to have corrected itself.

Since you have the off road, your tires are a little better. So, a little change in your driving style will save you some gas if you stay in 2WD. Those guys with 2WD in snowy regions will swear that a 4X4 is not needed if you know how to drive but its a nice feature to have when crap happens.