no engagement in any gear help please!

[big sally]

Yea it just looses engagement but the engine will stay on and the only way I am able to re engage is by shifting into 4wd and back into 2wd

 

[Honky Kong jr]

Sounds like your TC is jumping to neutral could be worn selector pads

 

[rpcraft]

Yeah its sounding like your issues are more related to the Transfer Case and its kind of common on really high mileage transfer cases. Sounds like its time to rebuild it but it might actually be more economical to search local craigslist or wrecking yards and see if you can come up with a good used one to swap in for a faster resolution.