After an almost 50 year hiatus, I am back to tinkering with cars. Now that I have the time, and a couple of bucks in the bank, it's a lot more fun. One aspect of the drive train I never paid much attention to was the differential, (rearend), it was just there and did it's job without much attention. Back in the day, it wasn't something that a 19 year old was going to invest a lot of money or time in to. If it didn't make Horse Power, it didn't matter ! Only now am I realizing just what the different differentials can do. After I bought my'89 RS and got it running properly. I noticed a howl coming from the differential. It was bad enough that I knew I was going to have to address it sooner or later. Of course one of the things I did was take the car out to a blacktop road in the country for a " Burn-Out" just to see what it could do. It's only a 305, but with no weight in the rear, and an open differential. it "Burned" quite well. I am pretty sure I could have sat there and literally burnt the tire to nothing, had I wanted to. Of course it was only one tire. I went on the hunt for another rear end and found what was purported to be a positive traction read end from an '86 Camaro. I brought it home and confirmed it was indeed a "posi" and I am in the process of installing it into my '89 RS, but I had questions. As I said, I never paid much attention to rear ends and knew nothing about them. I found this video on line, Everything you would want to know about rear ends, and then some. When I worked at a gas station as a kid, servicing cars, checking the rear end grease was common. You did it every time you changed the oil, and topped it off if need be. I didn't know then, and didn't know until about 30 minutes ago, that there were different lubes for different rear ends. Whooda Thunk?. This video, while a bit lengthy, is excellent. If you are a rear end novice, I highly recommend it. Just an FYI. Greg

 

Yup,gotta have that posilube in those limited slip rear ends with friction discs in them.
I learned that early on from my dad,had my first posi in 1972 when I was s 16 yo high school kid.