Is there such a thing as a drain plug for the transfer case or differentials that has a one-way valve where you can plug a tube in in order to fill the transfer case through the drain hole and not make a big mess? There does appear to be this kind of thing for the engine oil drain plug, but not sure if such a thing exists to replace any of the transmission plugs.

The point being, I'm going to replace my transfer case oil through the drain hole to avoid taking tons of stuff apart, which looks simple enough, but I would love to avoid the mess/fluid loss from removing the rubber stopper and quickly replacing the drain plug. And a one-way valve drain plug would make future services so much easier. I hope this makes sense.

 

Kind of repeating myself (from that "other forum"), the "cork and cheap fluid pump" method is really quick and easy, and honestly no messier than lots of other things we do regularly (and WAY cleaner than most oil changes). I suspect that even with a
"fill port drain plug" you're still going to be dealing with a stray squirt of fluid anyway (which won't be all that much less than the "cork method". But yeah, if you DO find such a thing, please post the info here as it would make the process a bit simpler in the future. For me, I'd have to measure the cost of the plug against the "extra time and effort" doing it the way I did (and given that it probably didn't add more than a minute, I'd be hard pressed to spend much to make it easier or cleaner)...