Question for everyone - I have the NP231 and I've read a lot about how you're not supposed to use it unless you need it. So when winter finally hits, when is it ok to use the 4WD? I live on gravel and it can get pretty bad in the snow and ice, but I also drive on pavement. Do I need to disengage everytime I hit pavement?

 

The NP231 should only be used on surfaces which you could loose traction, such as wet/offroad/gravel. Dont ever use it on dry pavement.

 

I have the NP231J also, part time only, don't run it on dry pavement.
I run 1.5 to 2 hrs trips daily, I run 4x4 in bad weather. If the pavement is snowy, icy, wet my experience is OK to run, I have 470000+ and still going strong. However if the weather improves and the roads are drying up, come back to 2wd. Dry pavement on part time 4x4 is pressure on your trans case and long term wear and failure. Don't worry about some intermittent dry patches when the weather is overall bad, just not prolonged use on the dry.

 

Thanks peep that answers my question