like it says, how do you put fluid in the differential, my rear end made a very sloppy clunking noise yesterday and i want to take the cover off to see if anything looks wrong but i cant find a fill plug or anything to put fluid back in....
It's on the driveshaft side of the differential, if I remember correctly. I haven't used it in a long time since I bought myself a rear end girdle with drain/fill plugs on it. You'll need some hose or an oil fill adapter with a hose on it at the very least, assuming you can maneuver the bottle of oil up above the differential. It's kind of tight. You might need to get one of those manual pumps to pump in the oil if you're having trouble.
There's a couple ways. Get a suction pump (like 5 bucks/autozone,etc.) or just get a tube, put it on the bottle, squeeze. I use a hand pump but either way works.
FYI, before you go add fluid, take the fill plug out and stick your pinky in the hole. Fluid should be level with the bottom of the hole.
The most common thing that I have seen cause "clunking" is the U-Joints. So I'd check them after checking the fluid level. If you have never replaced them, it could be your U-Joints.
On the passenger side axle tube, there is a ventcap that can be removed with a 15mm wrench.
I take that cap off , then thread the plastic tube from my 6 dollar "outboard gear oil" pump into the hole and fill that way.
Less messy than filling through the axle fill plug (located on the driver's side of the diff, facing the front of the car). I always find that the axle damper (dogbone) is in my way (though the dogbone is easy to remove)
I think I found the vent cap trick on this site - you may want to do a search.