NP208 Transfer Case diagnisis needed.

I run an 87 GMC 1500 4WD (lockable hubs) PU with a 305. It has a THM700R trans and a NP208 T-case. Occasionally while driving in 2WD The T-case jumps out of gear. I have to come to a complete stop put the
trans in netural. Shift the 4WD lever down to 4 Lo then back up to 4High. Then I can shift the trans back into gear and move on. It seems to happen on a longer drive like a hour or more. I had a dealer look at it and they couldn't get it to jump out. But it has happened to me 6 times now.
So what is it? The transfer case? Are they fairly straight forward?
Appreciate some help. Thanks
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It can omly be one of two things here as they are pretty simple. You either have a linkage problem and it is not fully engaging 2wd properly or there is a worn detent in the range selector internally and it it letting it pop out of high. Check linkages to make sure they are adjusted and worling correctly first. Given the age of the truck though I tend to think it is a internal Tcase problem with range selector. ----------------- The SnoMan www.thesnoman.com
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Maybe linkage out of adjustment from sagging trans mount?

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Just to close this out. I did pick up a rebuilt transfer case and that solved the problem. It was internal wear, and a rebuilt transfer case with the exchange was every bit as cheap as doing the rebuild myself.
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