How to Change the Differential Oil
1990-2000 Lexus LS400

This is a pretty simple procedure and doesn't take too long. The hardest part is just working under the car with a limited amount of space. If you have a lift or take the time to put the car up on 4 jack stands it's much easier. The car MUST be level to do this procedure. This procedure is the same for both first and second generation LS400's (1990-2000). Different years will take different amounts to fill, but regardless you will have to buy 2 quarts of oil.

Tools Needed:

• Socket wrench
• 10mm hex socket
• Torque wrench

Parts/Supplies Needed:

• 2 quarts of Gear Lube GL5 or equivalent, or SAE90
• 2 new crush washers for the drain & filler plugs, part = 12157-10010
• Gear lube pump
• Drain pan
• Shop towels

1) Park your car on a LEVEL surface. If your car is hot let it cool down. You will be working close to the exhaust pipes and they can be hot. Be careful! I jacked both the front and rear of my car up and put it on jack stands so I had some room to work.

2) Looking from the passenger's side of the car, here are the differential drain and filler plug locations. Put an oil drain pan under the differential along with some newspapers on the floor. Using a 10mm hex socket loosen and remove the filler plug first; a small amount of oil may drain out from this plug. Then loosen and remove the drain plug, the oil will drain out. These plugs are on tight and so you may need to use a breaker bar.

Draining

3) While the fluid is draining clean both plugs thoroughly. The drain plug has a magnet attached to it to catch metal shavings.

The gear lube pump makes this job simple and they cost less than $10 at auto stores.

4) Install the drain plug using a new crush washer and torque it to 36 ft-lb (49 Nm or 500 kg-cm), 39 ft-lb for 2nd gens. Add the new oil through the fill hole until it starts to drip out of the filler hole. The oil level should be equal to the bottom of the fill hole. Once the oil starts to drip out of the hole install the fill plug using a new crush washer and torque it to 36 ft-lb. Clean up the area and check for leaks. Capacity for 90-94 is: 1.4 quarts or 1.3 liters, it's a little more for later year LS's.

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