Auto 4wd, going into 4wd during low speed sharp turn?

[dmac156]

I have a few questions about the "auto" 4wd feature in my 2004 Explorer. I use 4x4 high on a regular basis in the winter, but have never noticed the auto 4x4 kicking in.

1) If the transfer case locks into 4wd automatically, does the light come on the dash saying it's in 4x4 high?
2) Like others I hear a clunking noise sometimes when I turn into a parking space. It seems like the 4wd could be kicking in, if so is it kicking into 4wd high? When does it disengage?

 

[Curtis]

I have a few questions about the "auto" 4wd feature in my 2004 Explorer. I use 4x4 high on a regular basis in the winter, but have never noticed the auto 4x4 kicking in.

1) If the transfer case locks into 4wd automatically, does the light come on the dash saying it's in 4x4 high?
2) Like others I hear a clunking noise sometimes when I turn into a parking space. It seems like the 4wd could be kicking in, if so is it kicking into 4wd high? When does it disengage?

The light on the dash (gauge cluster or 4x43 buttons) will not light when front wheels are engaged automatically.

When you go slow and make a tight turn, technically the front wheels are turning a different speed than the rear (due inner and outer wheel paths, inside wheels have a tighter circle path) and the auto system thinks you're slipping. So the front wheels are engaged.

When this happens, the front and rear wheels are now "locked" at the same speeds and therefore the truck will clunk or "hop" as it tries to move all wheels at the same time.

I found the trick is, when you are turning into a parking spot or making a u-turn, I just let the truck idle around the turn until I start to straighten the wheels. you wont get 4x4 engagement at idle speeds.