2019 C63: Locking differential oil change
I'm going to do my diff change this afternoon so I'll see if mine fit - hopefully I don't need a new one regardless.
I'm going to do my diff change this afternoon so I'll see if mine fit - hopefully I don't need a new one regardless.
Tools:
- 3/4 Box Wrench - preferably ratcheting
- Small flat head screw driver
- Oil catch tub
- Jack & Jack Stands
- 1.5 L (or so) gear oil - I used this one: https://smile.amazon.com/gp/product/B07KQFV3K8/
- Clean up rags
Process:
- Jack up the vehicle, level is best. Get enough room to weasel underneath it.
- Stick your oil catch tub under the diff. You'll be working from the front side of the diff, not the rear cover.
- Remove the upper plug with the 3/4 wrench, it's on the driver's side. See photos below.
- Find the drain plug on the passenger side, it has a brass temperature probe and some wires that you'll have to remove.
- Using the small screw driver, pull the white tab out a 1/4" and then wiggle the plug off the temperature sensor.
- Use the wrench to remove the plug, be ready for the diff fluid.
- After everything is drained, replace the drain plug and reconnect the wires and push back in the white locking tab.
- If you bought the diff oil I recommended in the materials, it comes with its own little pour hose. The container will fit up above the frame rails and can easily fill the diff.
- Dump 1 container in, then start pouring in the second until it starts to pour out the fill hole.
- Replace the fill plug.
- Wipe up the drips off the exhaust, and take the car off the stands.
- Have a beer, you did it!
Fill plug on the driver's side.
The drain plug on the passenger side.
The drain plug. Pull out on the little white tab to remove the sensor wires.
The two plugs, the drain plug with the sensor on my finger tips, the fill plug in my palm. Neither needed to be replaced unless you absolutely screw them up.
Last edited by bob_ham; Jun 22, 2019 at 11:02 PM.
Try as I might, I haven't been able to find a part number for the drain plug / sensor. If anyone can find it, please post it here so we have it for reference in the future.
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