wife got in the truck like normal today and drove to work half way there the truck wouldnt stay in gear every gear was a neutral i went to her job and messed around with it got it in 4wd truck started moving then put her back in 2wd and she rode fine go to get on it hard same thing. i again locked in 4wd then back in two she ran good then mile or so down the road again anyone else have this problem truck has 133k on it and havent had a lick of problem owned it for 4 years had 70k on it when i bought it thanks!

 

also forgot to mention it grinds when it starts to act up

 

Welcome to the forum...
I would be suspicious of the transmission, how does the fluid look?

 

Fliud was clean doesn't smell burnt

 

I'm no transmission expert but something to try may be to try each gear range 1 2 3 and D and see how it responds... might be worth checking the linkage to see if its damaged or out of position. a quick peek under the vehicle can answer that.

 

Could be the xfer case is shifting to neutral.