Hi, I am on a road trip in need of some immediate advice. My REAR differential on my 96 12v full size with 3:54 gears is leaking significant amounts of gear oil out of the TOP of the case where it looks like there is an electrical connector attached to the case. I cannot find anything in my manual about what this connector is and any diagram of the way it is sealed. Is there a gasket up there? If so, how do I go about replaceing it? Thanks!

 

there should be an o ring on the "fitting"

 

John, thanks for the reply. Do you have a diagram of the "fitting?" Just by looking at the connector I cannot tell how you would take that thing apart. It's not bolted on to the rear diff case or anything it just looks like its attatched somehow.

 

Looks like an O-ring around the diameter, and there should be a bolt straight up and down.

Here is a pic. Also looks like any decent auto parts store should have one in stock.

 

BTW, it is the RWAL sensor........

 

Also make sure the differential vent isn't plugged.
If so it would raise the pressure causing a leak.

 

Bill thanks for the pic. The o-ring looks in good shape when I pulled the sensor out today-not deteriorated at all. I put some RTV silicone on the plate that the sensor mounts to and just put it back on. Where is the vent for the diff? I do have a lot of crud on the diff that maybe I should clean off.

I also filled the rear differential up to the top of the fill hole. That's what the manaual said to do for trucks with the 10" gears. BUT, the diff really wasn't leaking until I took off on this road trip. I just did 800 miles yesterday and maybe that just made a small issue worse.

 

It sounds like your vent tube is plugged and is building pressure in the diff, follow the tubing and make sure its not pinched anywhere and that the vent on the end is not plugged.

 

I am not sure if this will help or not. My truck is a 2000 2500. If you look at the picture you will see a hose that loops over the axle and then hangs down. On my truck that is the axle/diff vent. The picture is taken from the rear so the hose is on the driver side of the axle. BTW - my hose no longer hangs down like that.