Advice on Pinion Yoke Change

Draining isn't necessary.Not a bad idea to suck out the old fluid and give it a change if it hasn't been apart in a long time.I just use a turkey baster and a piece of hose to get to the bottom.Loosening the nut may be a problem if you don't have air tools. You may have to use a puller but most of the time a few taps with a hammer will do.A 741 case pinion nut is torqued to 240 Foot lbs. Good luck.