'67 Monaco rear differential fluid change (is there a drain plug?)

MoPar~Man

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I don't see a drain plug, at least looking from the back side. Haven't been all the way under to look from the front. Is there a drain plug? I'm assuming if I manage to drain it, that regular 90 weight gear oil is what it takes?
 
8.75" Mopar rear end has a fill plug only. You can take a small length of tubing and suck out the old oil. Preferred method would be to pull the 3rd member and give the sump a good cleaning. Good time to also check the condition of the unit when it is out. This would also be a good time to repack the rear wheel bearings. If you happen to have a Spicer type rear end with the bolt on rear cover, pull the rear cover to change the fluid. As noted be sure to ad the sure grip additive if so equipped.

Dave
 
While on the subject, what do you think of this procedure?
Installing A Drain-Plug In The Differential Housing - Mopar Muscle Magazine

There haven't been any drain plugs for many decades. Probably because hand suction pumps became readily available to the service industry? With modern lubes, not a lot of real need to change rear axle fluids, under normal circumstances, these days. NOR do many people even considedr it!

Considering the higher viscusity of rear axle lubes, you can probably get as much out with the suction pump as if you allowed the housing to drain with a drain plug, I suspect.

Enjoy!
CBODY67
 
Ok, here are some pics:
diff1.jpgdiff2.jpgdiff3.jpg

If it's needed for identification, I can try to figure out the numbers stamped on the driver's side. I was able to get the plug off by putting a bottle jack under the wrench. I don't think I (or my dad) ever touched the diff fluid. I used a hand suction pump to pull out as much oil as I could. I had just used it about a month ago to do the same thing on my '01 2WD Ram (I didn't want to remove the cover). I got almost 2 L out of the Ram, but I'd guess only 250 ml out of the Monaco. Probably not good. I refilled it with about a liter, maybe 1.5. What is the capacity of this differential?
 
Alright, so if those are US pints, then 4.4 pints is almost exactly 2 liters. If I get this car on the road for a few short drives in the next week or so, before I put it back into storage I'll rig up something better to empty it and refill with new stuff.
 
Regardless of type of pints, fill level should be at or slightly below the fill plug opening while the car body is level.
 
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