If you have a late model Tcase you may well have the leak problem I ran into.
I rebuilt my t-case awhile back so I was a bit surprised to find a fairly consistent drip and puddle under the rig. And once I found the offending source of the drip I was a bit surprised.
There are a lot of places fluid can escape from. And this makes things a bit tricky in finding the source, especially on a really greasy, oily t-case, which is why I try to keep gear boxes wiped off.
At first I thought the gasket I had used on the output flange had let go and since I didn’t want to pull and re-seal it I started with some other possibilities. A couple of the bolts for the flange actually penetrate into the t-case so those got pulled and re-sealed with no luck.
After wiping things clean and driving the rig it appeared that the leak was coming from the top of the case. But I was able to eliminate the shifter hole as there was no fluid around it. Getting close now. Since I used a late model t-case out of a 62, there are several sensors that were removed or modified as I did not use them on my diesel. Two of the sensors were plugged with diff plugs as they are the same size.
But one of the sensors was a goofy thread. A 14mm with a 1.50 pitch. Not a lot of bolts available to fill this. So originally I just ground off the moving parts of the sensor and cut the wires then reinstalled it. Now this did work for a while but eventually the plastic that surrounded the wires and held back the oil finally got it’s share of the heat and vibration. Just to make sure I wrapped the plug with a piece of oil sorb material and drove the rig again. Lo and behold, the drip was gone but the sorb was soaked with oil. Now what?
Easier than I was expecting. My local Ace Hardware is a great store with a great bolt selection. But not only do they have bolts, they also have automotive stuff with lots of metric hardware as well. A quick dive into the oil pan plugs turned up one with just the threads I was looking for. Had a large flange and a gasket to go with it.
Installed it, drove to Oregon for over a 100 miles of wheeling and home again and the leak is gone. So if you have a mystery t-case leak on a later model be sure to eyeball the sensor. If your rig still uses the sensor, replace it. But if you are like me and just using the newer t-case that oil drain plug just may be your solution to that annoying drip.
