How do I check differential oil

[eddiepotts]

How do I check differential oil on my 83 prevost. I have looked all around it and only see what looks like an adjustment bolt with a lock nut. Out side of that there does not appear to be anything unless it is on the axle tube somewhere.

[luvrbus]

Eddie, the ones I have checked the plug is on the drivers side on the back close to the axle housing and about a 1 ft down from the vent  takes a 1/2 drive to remove it

[Seayfam]

I wouldn't know what an adjustment bolt with a lock nut on a rear diff would be for. If that bolt is about where a fill plug should be, I would pull it and see if that is where the plug was. It could be, someone messed up the threads on the housing and used a bolt with a locknut to keep it in there.

Good luck
Gary

[luvrbus]

Don't fool with the adjustment bolt that is the thrust adjustment for the ring gear keeps you ripping the teeth of the ring gear

good luck 

[eddiepotts]

Yeah I was not going to try and mess with that. I will crwl under again and look for the plug but I did not  even see a drain plug. I will keep looking.

[luvrbus]

The plug is just past the center of the housing on the drivers side   

good luck

[Lin]

It could be covered in gunk.  I think, and I am going by memory here, mine has a square head.

[TomC]

Once you do locate the fill plug-the oil should be up to the level of the fill plug just ready to spill out.  NOT a finger down.  Having the oil a finger down is enough to cause oil starvation.  Good Luck, TomC

[Lin]

That's useful, Tom.  I thought that if I could feel it, it was okay.

[luvrbus]

Lin, if you do not overflow the fill the axles have a tough time slinging enough oil for the wet hubs to run cool

good luck

[Rick 74 MC-8]

My MC-8 has 2 plugs one on the houseing and one on the pumpkin one is higher than
The other which on is right