I have been having some trouble with my NP242 lately. It is rediculously hard to switch from 4wd (any type) back into 2wd. You put the lever in and it stays 4wd for a long time. The only way I have successfully found to disengage the 4wd is by placing the truck in reverse and floor it for about a second or so. It disengages and I have 2wd again.
I also notice that when I put it in 4wd (FT) fulltime, it acts just as if it was in part time (PT). It is like I have a np231 with an extra lever pull to get it into 4wd. It engages in part time and full time but just acts like it is in part time only.
Any thoughts or explainations for this? Should I start with a master rebuild kit?
Have you tried adjusting the linkage? I found that for me if I get the tcase into neutral and then loosen the bolt on the linkage it works awesome and then tighten it of course. Keep in mind the 242 can be a pain to switch out of full time, I usually coast in neutral and then pull up a little on the e-brake and it pops right back into 2wd.
The great thing about UDP jokes is no one cares if you get them or not.
As for not coming out of 4wd into 2wd. Check your tire pressure, or uneven tire wear.
Mine would not come out of 4wd as you mentioned because I had two different manufacturers of tires front and back, I believe causing the t-case to bind slightly(242 is sensitive to this). As soon as I bought 4 new identical tires the problem went away.