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5 After And Filled
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Required Trinkets:
The fittings we chose are common “one touch” style fittings, but barbed or compression fittings are acceptable as well. We picked these up from our local pneumatic supplier to use ¼” NPT (pipe) threads. Make sure the line you choose will work with the fittings you have selected to avoid a mess. Beyond normal hand tools, a properly sized drill bit to match the tap for threading the holes will be required.3 of 6
Before:
After draining the oil out of our transfer case, we needed to select a location for our upper and lower holes. Here we chose to use the factory threaded fill hole, and found a suitable location for our lower fitting. If you run the risk of getting metal shavings into the transfer case, it may be better to disassemble and clean the entire unit to avoid contamination. Also ensure where you are drilling into does not have any critical parts behind it, and the metal is sturdy enough to be tapped.4 of 6
Tapping the Hole:
After drilling a 7/16 hole, we coated our tap flutes with grease to clean out any metal shavings produced and lubricated the tap. Pipe thread is tapered its entire length, so you may need to test fit your fittings a few times to get the depth right.5 of 6
Fittings Installed:
The one touch 90* fittings we selected come with thread sealant already applied. The elbows on the fittings are adjustable so we could clock them into any position required. Our upper hole was originally ½” NPT, so we had to pick up a reducer to go to ¼” NPT. Alternately, you could also tie into the vent line, or drill and tap another hole in your transfer case for the upper hole.6 of 6
After and Filled:
Installing the line with these fitting is as easy as bottoming out the hose into the fitting, and pulling back until it “clicks” into place. After cleaning the inside of the case of any stray metal filings and sealing it up, it was time to test our handiwork with some fresh 80-W90. It’s best to mark on the hose with a sharpie or tywrap to monitor oil levels during the wheeling season.Story & Photos by Bryan Irons
Filling the oil level in a transfer case like our Dana 300 is pretty easy. Pump it full of lube until it reaches the bottom of the fill hole. But what if you have clocked your transfer case into a different position? Now putting oil into it until it reaches the bottom of the fill hole would be just too much lube. Between parasitic losses and excess oil spewing out of the vent tube, you have a mess to contend with.
With just a couple of pneumatic fittings and some line, we made a handy sight tube to be able to check our oil level at a glance. This setup also lets us fill our transfer case to the proper level after an oil change. You do change you transfer case oil, don’t you?