Rear Differential service

Can anyone suggest a link to a website that might have step by step procedures for draining, cleaning, and refilling the rear differential in my 1975 coupe w /auto trans. None of my new manuals are very detailed. They just say to drain the differential.
Thanks for your help!
Scott

That pretty much sums it up.  Drain it, fill it.  Include some of the GM positrac/limited slip conditioner as you fill it up.  Pretty straightforward.

Thanks
Specifically how do you remove the fluid? The leaf spring covers the rear cover an is bolted to it. There is no drain plug, only a filler port.

I bought something that looks like a turkey baster with some fuel line on it from my local parts store years ago. Works well, all it takes is patience.

Yeah, it's a pain to do it, but you have to use some kind of suction gun to draw the old lube out. It works much better if you do it when the diff. is hot. That thins the lube out, and makes it easier to 'suck' out. You can buy a suction gun specifically for this at most parts houses. There is also an electric sucker that you can just plug in, and let it do the work. (It's basically just a modified 'lectric fuel pump.) Check with you favorite parts house, and tell them what you're wanting to do.
Be sure to add the posi additive first when you refill the diff., so you'll have room to get it all in.
Adams' Apple38546.8203819444

Thanks a bunch guys! You have put my mind at ease. I thought I was missing something!
Scott

Try looking at Autozone, they have a pump that is orange and it will suck the old fluid out. Be sure to add the limited slip additive first then put the gear oil in. Have fun. 

Just did mine yesterday........

Valvoline gear oil + 1 Tube of posi fluid additive. 

I used a hand held suction gun that did looke like a turkey baster (as Luke said).....Worked great!  Pretty easy with the car on a lift. 

Filli it slowly until it begins to run out, but do not overfill.

Anthony

And if you jack the car up, doing it on the ground, you'll overfill it if it's jacked up from the passenger side   --   like I did  drained it once I let the jack down with the plug out.

Check Corvette Central. They have a kit to drill and tap the strut support and install a plug for draining the rear.I did my car last year and it worked fine, just follow the directions.