Inside rear wheel of the turn is skidding across the pavement?

RANDYJA

MEMBER
2005 DODGE RAM
V8
4WD
AUTOMATIC
40,000 MILES

I have a 2005 Dodge Ram 1500 4WD truck with a limited-slip differential. When the 4WD is engaged, and I turn at low speeds (which is when it is noticed, though may happen at higher speeds as well), observers notice that the inside rear wheel of the turn is skidding across the pavement. Is this normal behavior? I realize that a limited-slip differential will provide some torque redistribution because of the disparity of wheel turn rates, but I'm a little concerned that it's not allowing the inside tire of the turn to slow enough to not slip or skid across the pavement. This is most noticeable during non-dry pavement conditions, which allows the wheel to skid or slip more readily as opposed to dry pavement.

My questions are these:

1. Is this normal behavior?
2. What kind of bind or stress is being placed on these parts during turns like this? If the turn couldn't slip, could it break something?

Thanks

1 Reply

CARADIODOC

MECHANIC
33,916 POSTS

You're describing normal behavior of the wheels, but not normal driving. Four-wheel-drive should never be used on dry pavement. That forces both axles to rotate at the same speed. That isn't an issue when driving perfectly straight ahead, but with even the slightest turning, as in when changing lanes, the two driveshafts want to turn at different speeds. The same with the two wheels on each axle. That is the entire reason differentials are used in drive axles. Those allow the two wheels to rotate at different speeds. Placing the transfer case in two-wheel-drive allows the two differentials to rotate at independent speeds.

As far as breaking something, the driveshafts and the axle shafts are having a real lot of twisting stress placed on them. A slipping tire is what's preventing an axle shaft or a universal joint from breaking. This also puts a lot of stress on the transfer case. I've already caught myself forgetting to shift back into two-wheel-drive after plowing through the show drifts in my driveway. Worrying about the stresses on the system makes the hair stand up on the back of my neck.

Most newer models have an additional "automatic" four-wheel-drive mode that allows the system to engage momentarily on its own only when it's needed. I've used that feature a few times, but only when driving on snow-covered roads. Without it, my truck has a tendency to fish-tail on snow very easily, especially after becoming accustomed to driving front-wheel-drive Caravans for many years and being able to drive through anything without even thinking about it.