Question about 4 wheel drive

[arouth]

My parents got into a car wreck last week (everyone is fine), and they are asking for my help in buying a new car. They are thinking of either a v6 4runner, an explorer, or an expedition.

I'm a little confused as to how 4 wheel drive works. I have AWD on my 4runner, and it is great in the snow, but I never touch it.

I called a dealership and they said with 4 wheel drive you can engage it at like 45 miles per hour and then you can use it all you want. Is that totally true? I'm wondering if they could just leave it engaged permanently or would there be any damage by doing that?

Any advice would be appreciated.

Thanks

 

[RonMAIDEN]

On slick surfaces AWD is superior to real 4wd since just like the Subi commercials say that it pulls power away from teh wheel that slips and applys it to the wheels with grip and it's all done by the ECU. With 4wd you must control the slipping and 4wd is more for the deep snow or off road. If my 4Runner hasd the multi-mode auto I'd use nothing but AWD in 90% of the snow and ice we see here.

 

[Thai]

Someone correct me, i think that you can make the switch from 2wd to 4wd up to 62 mph. You can make the switch back from 4wd to 2wd at any speed.

Yes, you can leave your 4runner in 4wd all day long. Some people even suggest doing this to get more even wear from your tires...not sure if it's true, but i can see why.

But, remember, at high speed, it is the stability control and brake assist that will save you. AWD does help...and having both is better than having one or the other.

 

[JB.]

If there is anything here someone feels I have wrong, please let me know.

The V6 has the Torsen center diff, too.

 

[Uneek]

If there is anything here someone feels I have wrong, please let me know.

Cheers,

Not quite, at least not for 4th gen 4Runners.

The V8 and the V6 have the same Torsen limited-slip center differential. The V6 adds the ability to be driving in 2WD (RWD) mode only, where as the on the V8 it's full-time 4WD. The 4th gen doesn't have a part-time 4WD system, so it can be driven in 4WD mode all day long and on any type of road surface.

Under normal conditions, it has a 40/60 front/rear power split. If the front wheels are slipping, it can divert up to 71% of power to the rear wheels. If the rear wheels slip, it is adjusted to 53/47 front/rear power split.

 

[Thai]

The V6 Runners have Multi-Mode 4wd which is more or less Part-Time 4WD with a Center Diff. This diff is an electronically controlled clutch which can vary power up to 50% to the front. When you have your Runner in Auto mode, you truck will send 100% of the power to the rear unless it senses slippage, then it will start to push some of the power to the front. As your vehicle speeds up, forward traction becomes less of a problem and as Thai mentioned stability becomes more important. As you do speed up, the truck will begin to let the power delivery fall back to the rear of the truck and in the end your truck will be back with 100% of the power to the rear. If you are at highway speeds even in Auto mode, you are most likley only putting power to the rear wheels. This process will repeat though if your truck starts to detect slippage in the rear. There is a big difference if you have your truck in 4WD mode than Auto. In 4WD, you truck is now in 4WD with your center diff locked. You do not want to be driving like this on pavement because it is extremely hard on the driveline. This is why the manual doesn't recommend 4WD after such mentioned speeds.

This whole paragraph is all wrong.:bash: I really don't know where to correct you.

V6 and V8 4wd 4runners all share the mechanical Torsen center diff. When you go into 4wd in a V6 model, it acts THE SAME as the V8. You can go into 4wd WITHOUT locking the center diff.

You need to review this: http://www.toyota-4runner.org/showthread.php?threadid=12

 

[Jeff Kleb]

My 4Runner is a V6 model and doesn't have any type of "Auto Mode" for the 4x4 system. I have 2HI, 4HI and 4LO - nothing else.

I have only used the 4x4 twice on snowy roads, but drive about 20 miles every other few weeks in 4HI mode, just to keep the system lubricated (the stealer recommended this practice).

One of my managers at work has a V8 4Runner and his only has 4HI and 4LO.....no two-wheel-drive option at all. Wow.....that's gotta make the fuel economy take a beating.
:bash:

I am sure the V8 is a fine machine, but my V6 fills the bill just fine. I am not towing anything and the V6 can get up and go like nobody's business.
:bigok:

Whatever you decide for the 4Runner, it appears as though there is not a "bad choice" to make.