How to change differential fluid on a 99 automatic Options

[Richardkwon]

First of all, is there a differential unit on these cars? Mine is a 1999 automatic transmission. I think I see it near the automatic transmission drain plug. I think the drain plug is at the bottom but where is the filler plug and what type of fluid?

[Smaay]

if you have an automatic, you need to take it to a shop to have the fluid changed. it needs to be pressure flushed. if you just drain the oil and then fill you only change the case oil, you dont change any of the oil thats in the torque converter

[Richardkwon]

As for the automatic transmission fluid, I've changed it 8 times and finally the fluid is starting to come out bright red. I'm going to change it one more time and most of the old fluid will be flushed out by then.

The differential fill plug can be undone by using a ratchet with a long extension with 17mm socket. I had to use a breaker bar to get the upper plug undone because there's not much room underneath to get any leverage with just a regular ratchet. Jack up the entire car so that it is level. The drain plug is undone with a 10mm hex wrench. I drained mine and only 1/4 of dark black fluid came out. No wonder why I was hearing a slight whine. Regular automatic transmission 1.5 quarts of Dexron fluid is fine. I used a manual pump to get the fluid in from beneath as getting a hose from the top is really really difficult. I was really thinking of just blowing this off but I'm glad I did it. My car has only 70K on it so if you have not changed your differential fluid yet, do it.

This post has been edited by Richardkwon: Oct 24, 2014 - 7:48 PM