Cool. I'll look for the stamp. I'm pretty sure it's an open diff. The wheels rotate opposite each other. But the driveshaft rotates if I rotate one wheel either clockwise or counter clockwise, I can't remember which. I think my diff needs oil and/or its shot. I suppose I should have checked/changed the oil before driving it, but I just couldn't help myself.Your 72 came with an open 3.64. You wouldn’t want a 3.07 with an overdrive trans. Euro coupes had a 3.45 as they had more HP, the US 2800CS also had a 3.45 but they are hard to find. If yours has a stamped or painted S it is limited slip. Ratio and stamp is on passenger side of diff on the flat boss beneath and just rearward of the half shaft. 40:11 is 3.64
Here is my 3.64. Look for this on the casing :Cool. I'll look for the stamp. I'm pretty sure it's an open diff. The wheels rotate opposite each other. But the driveshaft rotates if I rotate one wheel either clockwise or counter clockwise, I can't remember which. I think my diff needs oil and/or its shot. I suppose I should have checked/changed the oil before driving it, but I just couldn't help myself.
What does the no. 3 mean?Here is my 3.64. Look for this on the casing :
View attachment 86926
No clue, some random casting number?What does the no. 3 mean?
Thanks for the stamping location. Now I know where to look to see what LSD is in my car. About 3000 RPM was 80 MPH ,and 4000 RPM was 100MPH in 5th gear.