M1028a2 differential drain

[319cssb]

I was checking or rather replacing the oil in the differentials. I could find a fill but not a drain plug. It looked like there is a channel from one of the cover bolts. There was a bunch of silicone sealer in the bolt holes , and so even with some probing i didnt get any oil to come out. I ended up pumping the oil out. I which i dont like doing. I rather see it drain out by gravity and flush any possible pieces out.
Still curious of how they are supposed to be drained. The M1009 has drain plugs.

 

[n8roro]

The m1009 you need to pop the diff cover to drain then you can mop out the thick goop and clean the magnets. The 1028 could be the same, but I'm not sure.

 

[cucvmule]

I pull the covers at 50K and change out gear oil, and check for wear, debris. Or if I am in deep water stopped, over my wheels. Then I pull pan to check for water, or pull the fill plug and take a sample, inspect. I also lengthened my vent hoses higher and put on new vent caps. For the price of a gasket or silicon it is wise to check for any problem. Leaking axle seals cause all kind of problems. Fresh 80w90 and you are done.

Rear axle hub seals, pinion seal, if you see no oil leakage then ok.
Front D60 Axle pinion seal, obvious leaking. Inner axle seals, hard to detect leaking gear oil after level lowers below axles. But water intrusion is easily done.

The only time I like to smell gear oil is during maintenance.

Everyone has their own way, and the manual way. But always error on the side of caution. Over information?