05 T4R best SUV?

[boston_kevin]

They had a feature with a manual tranny where you could put it in 1st gear, 4WD Lo, and use the starter motor to "crank" the vehicle inch by inch, giving an effective crawl of about 1 inch per second (not sure what the ratio would be) The starter motor had a torque output that was capable of actually crawling the vehicle up a near vertical embankment for about 30 seconds. After that, you had to let the starter rest and the battery recover, but you moved the vehicle about 4 feet which was enough to get you unstuck or past a dangerous obstacle. It was an awesome feature to have when crawling over particularly dangerous areas or through thick mud if one got stuck. (I think this was a leftover from the military days)

 

[SevenJ]

OK, I've been reading about lockers for a while and while I've tried to research them, I still need a "lockers for dummies" explanation. I was just on the jeep website and the wrangler has front and rear lockers. The 4runner has a locking center differential? Is this correct? What is the difference between the two and why are the lockers better off road.

Should be no surprise that i've never had my 4runner off-road.

 

[Thai]

Center diff lock = locks the front and rear axle together; torque goes to both axles equally.

In the Jeep Rubicon, if you're in 4HI or 4LO, then the front and rear axles are locked together (similar effect to above).

What makes the Rubicon an even better off-roader is that it also has lockers on the front and rear axles. So, torque is equally distributed to every single wheel.

In the 4runner 4wd, the center diff is lockable. So, torque goes to front and rear axle equally when locked. Torque distribution in the front axle is managed by traction control. That is, if one of the front wheel is slipping (thus no traction), then ABS will apply the brakes to the slipping wheel, allowing for the other front wheel to get some power. In the rear axle, it's the same thing...traction control distributes torque between the rear wheels.

In the Rubicon, torque is equally distributed to the front and rear axles when in 4Hi or 4Lo. In the front axle, the locker will equally distribute the torque to each wheel. Same for the rear axle. A locker is more efficient than traction control because it "LOCKS" the wheels together. Traction control has to rely on slippage before it acts (reactive vs. proactive in the locker)...and it can never achieve the true equal torque distribution of a locker. Traction control works quite well, but it is just not as efficient. Traction control, however, is as effective as any limited-slip differential (LSD) on the market.

 

[SevenJ]

Thanks Thai, that was exactly what I was looking for.