how do i check oil level on the transfer case attached to transmission ?

http://www.coloradok5.com/jbconversions/main.jpg

NP241 case. Look at picture above. Lower left of the t-case is the drain plug. Up and slightly to the right (the same looking bolt) is the fill point.

Fill the t-case through this upper hole till fluid starts to come out (done on level ground), then replace plug. I'm not sure if yours holds ATF or gear lube double check before refill (was it red when it came out? then it auto tranny fluid), I do know that the 96+ GM use ATF in the t-case.

First two replies are right, except GM didn't use the square headed plug this time. Using a 3/8" or 1/2" is common on most all t-case plugs. My 97 GM does. So does my '01 Dodge as well as did my '77 Jeep.

There should be a plug somewhere on the side of the transfer case that has a square hole in it, you can place a 3/8 drive ratchet directly into the plug and just turn it out like a normal bolt. fill the case with the recommended fluid until it begins running back out of the hole. replace the plug and your done.

For any circulate case i've got ever touched, the only thank you to confirm the case fluid point grew to become into from below the vehicle. All have a plug that desires to be got rid of, and the point is to the backside of that hollow.

frank e got you on the right track it should be 1/2 way up the drivers side case