Approx 96,000 miles on a 2002 Mercury Mountaineer and problem has started that
sounds like a 4-wheel drive problem. Taking off from a stop, turning the
steering wheel, I get a sound that is much like the "shudder" that comes with
taking off in gravel with 4-wheel drive engaged in my Nisson that has manual 4
wheel drive.



Dealer says they think that problem will be solved by my
replacing 4 rather new Michelin tires because of uneven wear (perhaps 1/8th inch
on one tire) causing AWD sensor to think one wheel isn't turning as fast as the
others and kicking 4WD into action.



The tires I replaced were really worn
unevenly and problem should have showed up with them as well, but it didn't. The
problem occurs after driving for a couple hundred miles and not when leaving the
garage.



Any ideas to explore?

Thanks

Dale

sounds like 1 of your transfer case speed sensors is going bad there are 2 both located on thw tansfer case if one stops workinf then the car will think it need 4 wheel drive need to have sensors watched with scanner to see which one or both are quitting good luck

Thanks for the note...I'll give this a try. Another
forum expert advises that my problem might be
the sensor - says it might malfunction after it
heats up during several hundred mile drive. I don't
have the problem with short travel 100 miles or
less. Thanks for your thoughts on this. keep up
the good work! Dale