i have a 76 cutlass supreme brougham 455 ,th-400, not sure on rear end gears 12bolt 2way limited slip i think . maybe 1 1/2 limited slip . very nice car all numbers seem to match . i did change the carb . and the passenger door was damaged by a deer . so i had to by another 76 to change the door

 

my car

 

Not sure I understand that, I always thought there were "open" rear gears or "limited slip" ones. Are there more kinds? By the way, very nice car.

 

well with any cars there are 1 way limited 1.5 way and a 2 way limited and posy as i understand it . my car has the rear end tag i just dont recall what it said .

 

I'm probably talking out my kiester but my dad bought an 85 1 ton jimmy with a special diff. As I recall he called it a locking differential. The story is the unit acts as an open, until it encounters slip or loss of traction. Once the tire turns a preset amount, the other side engages, and both sides pull. I was a kid when he explaned this to me so I might have details wrong, but remember being there when the truck almost jumped off the jack, the day he decided to test it out. The tires spun opposite when in the air. Sorry if I got too wordy. Any way, he may have been talking about a similar unit, I don,t know anything about diffs though