Any issues accidently driving in 4WD?

Eh, if you need 4wd, then there's not enough traction to cause an issue. Or, if you're binding the drivetrain, then you don't need to be in 4wd (in my opinion).

I think tires are the most important consideration for snow (since they help you turn and stop safely as well), then you can worry about number of drive wheels later. (Although there is merit to driving slowly in 4wd, where you'd have to get some momentum in 2wd, which is more dangerous on slippery roads).

 

There is no centra diff on the partime 4wd systems.. just a solid driveshaft from transfer case to the rear diff

 

Yes, I read a study that showed that four good snow tires are often better than AWD or 4WD on snow covered roads, especially when it comes to stopping distance and turning the vehicle. I drove 2WD (RWD) vehicles for years with four snow tires in northern Vermont and never had a problem. Unfortunately, people buy part-time 4WD 4Runners thinking that they can just put it into 4WD on snowy days and drive on asphalt roads. These roads are typically plowed and are not slippery and snow covered all the time, thus leading to excessive wear and damage to the vehicle. Better to just buy the Limited with full-time 4WD, not use the part-time 4WD, or buy a 2WD 4Runner and be sure to have four good snow tires.

 

If it’s a 4th Gen, they can.

 

Short answer, the 5th gen part-time 4wd does not have a differential in the transfer case.

Without a differential in the transfer case, the front and rear driveshafts are mechanically locked to turn at the same speed, which will cause bind whenever you are dry paved surfaces The binding is caused because front wheels don’t always rotate at same speed as the rears while steering the vehicle through turns. Off-road, this binding is scrubbed off at the tires. But on dry roads, the tires have too much traction, so those forces just go straight into the axles, gears, and driveshafts.

The multi-mode transfer case in the 4th gens really sounds like the best configuration ever. It comes with a center diff-locker which disables the center diff and allows greater traction when necessary. And it’s basically a full-time 4wd system that lets you use 2wd (which the current Limiteds can’t do).