Can anyone tell me how to check the rear end fluid in a 69, how to drain it and how to fill it?
Seems like I just didn't find the plugs I need to remove. Any idea where they are?
Thanks,
Doug

Take the cover off to drain. There is a pipe plug you remove to fill. Scrape the sludge out when you take the cover off

If posi refill with real oil not synthetic and use some GM posi additive. Synthetic made my clutch plates chatter.

The fill plug is on the right side, forward of center just about level with the bottom of the axle tube. Proper oil level is with the oil just at the bottom of the fill hole. As Bob says you have to take the cover off to drain, if you leave the top bolt in and just loosen it enough to separate the cover at the bottom until the oil drains, it may make the job a bit less messy. I also agree with Dennis, I only use regular 80/90 hypoid oil and avoid synthetic. Some gear oil comes with posi trac fluid additive already mixed in, but I don't think it's enough of a percentage. I used it but added some additional posi additive as well.

Seems like a big hassle having to take the cover off rather than just open a drain plug, but at least with the cover off you can get all the crud out and also check over the diff while your at it. Things do come loose once in a while.

thanks to all who answered and especially for the photo. Laying on my back under the car I somehow missed the plug! I appreciate the help.
Doug