Hi All,

I wanted to post some information I gained today about changing the differential fluid in a 1984 Toyota 4Runner. Of course, this might be helpful to maybe 2 people in the entire world, but even still...

One problem you may run into is the fact that Toyota no longer manufactures differential *fill* plugs for 84 4Runners. I'm not sure about any other years and I'm not sure about the differential *drain* plugs either.

However, if you need a new differential fill plug like I did, you can go to a CAP or Advanced Auto Parts and get a generic oil drain plug. Just take off your old one from the front or back differential (they are the same plug) and bring it into the store to match the threads. The one that worked for me was "Oil-tite" brand, oil drain plug, with the number M18-1.50 on the box. I think this plug is made by this company called Dorman: dormanproducts.com

part number on website might be 65220

OK, so I finally got the right plug. Now I had to deal with the next problem which was getting the drain plug off. I had painted POR-15 under the entire underneath of my 4Runner, including the plug. I could not get this off. I tried for an hour or two and then brought to my friendly neighborhood rip-off garage. They charged me 50 bucks to get the plug off. But, whatever. At least I got it off.

Then I went to Advanced Auto Parts. Picked up 80w-90 Gear oil (check to make sure this is the correct weight, but I'm pretty sure this is what I used). I also purchased a suction device. Then you just suck out the old gear oil. (The gear oil in the front was pretty black. The oil in back was not too bad.). This took about an hour to just suck out all of the oil. The faster and better way to do this, of course, is to drain this from the differential drain plug, but I didn't have the correct tool to do this. I think the differential drain plug is magnitized and it collects misc metal chips from the gear. It's best to drain out through the plug so you know you get all of the oil out and then swipe all the metal off the magnet, but, ya know. You do what you can do.

So, once you've got all the old oil out, you squirt the new oil in. I think the front differential gasket takes around 4.5 liters and the back takes 4. But I'd recommend buying 2 gallons on the stuff to be on the safe side. If you're like me you're going to be squirting the crap everywhere and you'll use some up and pollute the environment a bit. It's all good.

Ya, so squirt in the new oil. Try to do this when your truck is parked at a level place. Then when the differential case doesn't take any more and it spills out onto the ground and eventually drains down a sewer and kills lots of fish, you're good!

Hope this helps!