Rear end gear lube

[Flight102C3]

Good morning!  What are we using for gear oil in rear end? 80w 90. I have a 102C3

[Utahclaimjumper]

75W90 Synthetic.>>>D

[Jim Eh.]

Are you topping up or replacing?

[sledhead]

so how many gallons are in there if I want to drain and change it ?

thanks   dave

[GnarlyBus]

My MC9 has takes 4.5 gallons. The manual lists it right at then end of the rear axle chapter on the specs page. I'm getting a 5 gallon bucket when I do mine.

[luvrbus]

Use the GL-5 rated 75/80 the GL-1 through GL-4 is old  school

[Iceni John]

Use the GL-5 rated 75/80 the GL-1 through GL-4 is old  school

I've been using GL-5 85W/140, which is what my Rockwell manual recommends for the temperatures here in SoCal.   I also use it for the front and rear hubs.   Is that OK?

John 

[chessie4905]

We used 90/140  Lubrication Engineers synthetic in our 4104. It flows like molasses at room temperature.

[Flight102C3]

Sorry ended up out of town working! Did wheel end work. Drained all. Thinking 80w90 old school. Thanks

[bevans6]

I like Lucas Hub Oil for oiled hubs, it is very persistent, sticks to the bearings, and resists leaking.  Gear oil has extreme pressure additives that aren't needed for roller bearings.  MCI recommends SAE 30 Engine Oil in the front hubs.