I recently developed a problem with my 4wd on my 92 automatic 3.0 runner. I lock my hubs, put it in 4wd and attempt to make a u-turn my 4runner resists turning entirely. I crank the wheel and give it gas, but it doesn't really move. There is grinding and I can hear a noise coming from inside by the trans shifter. I have no idea what the problem is, a little help would be nice

 

when was the last time the tires were rotated?

 

Last week

 

and you realize that the 4wd on your yota turns the front and rear axles at the same speed? and when turning, the front wheels turn a smaller radius circle than the rear wheels which means that the front and rear will turn at different speeds?

 

and I'm guessing that you know that since the front turns a smaller radius than the rear, the front needs to slip or slide a bit and can't do that if you're getting good traction?

 

and I'm also guessing that a U-Turn (or at least "full steering lock") is about as extreme as you can get to cause the front and rear to turn at different speeds?

 

It will act like that if your trying tun 4wd on pavement or in a high-traction situation, its called driveline bind.

Does the 4x4 work fine in a straight line?

 

Well guess im an idiot, i tried this out on some packed dirt. thanks guys

 

Its perfectly normal. Since the wheels want to turn at the same rate, when under full traction, it makes it harder to move and harder to turn.

 

i would think the rear wheels would have the smaller radius. when making a sharp left, the driver's side rear wheel would be the "pivot" point of the turn, requiring it to have to travel the least distance.