I was just wondering how many of us change your rear diff fluid and when?
I'm getting ready to do mine. I have owned her for just over 50k miles and I have never changed it or even remember seeing it talked about. Thought it strange.
Anyway, probably going with two liters of 75W-90 Full Synthetic gear oil, grade V. About $16.00 a liter. That seems to be the recommendations instead of the severely overpriced OEM gear oil.
So, I have crush washers on the way, and gear oil. Thats it.
My only concern is the severe spec for filling level. 0.20 inches/0-5mm from the lip of the fill hole. How do you check level of the car? Titled forward or backward etc.,ould affect the oil level? Am I over thinking this? Thanks.

Paul

 

I changed mine at 100,000 miles. I purchased the car at 93,000 miles. It looked like it was never done before, original crush washers, etc. The oil that drained out was very clean. Mine had the Synthetic Oil tag so I used 75W-90 Syn GL5 oil.

As for the correct fill amount, the book says 1.42 quarts. To check for the proper fill level ensure the vehicle is level, then stick the tip of your little finger into the fill hole. You should be able to touch the oil giving you the desired .2 inches below the fill hole.

 

What if you put it on four cinder blocks? one block under each tire (maybe 2 for height) That way you know it will be level, PLUS it will raise your redneck score. Just make sure to keep your jackstands in place for safety

This isn't exactly what i was thinking, but the same basic idea

 

I haven't' done it on my SC yet because I've only had it a week, but I will be changing the diff oil soon. What I have done on other cars in the past is drive the front wheels onto some car ramps, then jack up the rear and place 1-2 foot long pieces of 2x6 lumber under the rear wheels until the vehicle is level. You may need a few thinner pieces of wood as well. You can check the level by placing a carpenters level on the doorsill when the door is open.
Loosen your fill plug first (to make sure it will open) and then open the drain plug and let the old oil drain out. I usually take the car for a spin before I drain it to warm up the diff oil. Once most of the old oil is out, I like to put a little new oil in the fill hole and allow it to help wash the rest of the old oil out.
Once you're happy with the draining, replace your drain plug using a new crush washer and torque the fill plug to specs (not sure what Lexus specs are as I just got the car, but you should be able to google them. Probably around 35 ftlbs or so).
Fill your diff through the fill hole. I like to fill it until the new oil just starts running out and if the manufacturer says it should be a certain amount below the fill hole I take a syringe (you can buy these at local auto parts places) and suck out just enough to meet the requirements. Replace the fill plug with a new crush washer and torque to spec. Done.

 

Bingo. That's exactly what I did. Ramps in the front, jacked her up in the rear to level with jack stands.
If you have a lift, its MUCH easier.

Paul