4 wheel dive PLEASE HELP

[zebiraross]

I have a 1994 S-10 4 wheel drive ls. I recently had the transmission rebuilt by a reputable shade tree mechanic (if there is such a thing). Anway when pushing the 4 wheel drive buttons, It shifts (or gears down)to 4 wheel low of hi, but the 4 wheel drive doesn't work?? Is there a reason it would be gearing down but not engaging the 4 wheel drive. Any info would be appreciated.
Thanks

[zebiraross]

Also, it's a manual transmission

[smokey041369]

this may help on my old 95 blazer there was a unit the passenger side front ( at the bottom) of the engine compartment that has a vacuum line check to see if the vac line is disconnected and on the transfer there are vac lines also check to see if they are disconnected

[zebiraross]

thanks for the advice, I'll give it a look