As simple as it may seem, changing your differential oil often perplexes some people and intimidates others. We're here to show you it really is straight forward. All you need are some basic hand tools and some fresh gear oil.
Start by placing the car on jack stands on all four corners. NEVER crawl under the car without jack stands, jacks do fail and the end result can be catastrophic.
Crawl underneath the car and locate the drain plug. You can't miss it. Grab a 1/4 inch breaker bar or ratchet and crack the plug loose.
Make sure you have an oil pan handy and remove the drain plug. Let the oil drain.
Check the drain plug for residue and shavings on the magnet. If there are excessive shavings then it's a smart idea to have your diff checked out. Otherwise wipe it off and reinstall it if all the oil has drained out.
Tighten the drain plug to 29-43 ft/lbs or if you don't have a torque wrench use common sense and snug it up until you feel it's tight.
On the side of the diff you'll find a second plug. This is used to fill the diff up. Crack it loose and remove the filler plug.
This is what we will be using to fill the diff with fluid. You can use whatever you have laying around as long as you can attach a hose of decent length to it.
Our gear oil of choice for our stock equipped VLSD was Royal Purple Synthetic Max-Gear 75W-90. You'll need just over a quart of it so two bottles will be enough. The diff takes about 1.25-1.8 quarts/liters.
Take the plastic tube and run it through the wheel well into the diff filler plug opening.
Pour the oil into your fill tube and let start pouring in.
As the oil is pouring in, you'll want to periodically check underneath to see if oil is starting to run out of the filler plug hole. If it is then you know it's at capacity and you can stop pouring oil in. Otherwise top it up to the recommended capacity and stop.
Screw the filler plug back into the diff. Wipe it off and you're done. Now that wasn't so hard was it?
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