<font face="Comic Sans MS">It depends directly upon conditions. On the sand dunes I run in either 1st or 2nd gear with the t-case in either 2wd or 4wd high (depending on if i'm climbing the really big hills or not)...
Mud, I tend to run low range, 3rd gear (manual tranny).
If you have an automatic transmission and unless you have a manual valve body in your auto tranny (so it won't shift until you shift it), it'll usually pick the right gear for you... [img]/wwwthreads_images/icons/cool.gif[/img]</font>
When I'm froading in my automatic I'm in overdrive. In fact, It never comes out of overdrive unless I'm going to park or reverse! I'm not sure if this is a good thing or not, but I haven't hurt anything yet and it's still running great. Plus, you can go really fast or throw alot of mud! This may not even apply to your truck, but It's what I do in my 4x2.