I lubed the driveshaft yoke a the transfer case last fall to help with the clunk the others have seen when starting out from a stop. The grease helped some, but not completely. I noticed when I put it back together after greasing that it was very hard to push the yoke back into place from the grease sealing / trapping air in the yoke. The whole yoke assembly would slide much easier on the output shaft if there was an air vent hole in the yoke. Have others noticed the same issue?

Yes i just did the procedure this weekend. I just moved the drive shaft in and out and actually pulled it off to remove some of the grease. Hopefully you used the gm stuff or a good marine grease similar to the kind you use on props.