I'm trying to find out if I have an auto or manual diff so I can sell it. According to the driveshaft flange it's an auto but if I turn the flange it takes just over 4 turns for one turn of the axle. I decided to take it apart and look. From the research I did I found that the 3.90 has a 43/11 gear ratio (ring gear/ pinion gear) and the 4.10 is 41/10. I counted mine and it's 40/9. Now if you divide that it's a 4.4. I have never heard of a 4.4 diff. Anyone have any idea what I have? I am lost.

 

Might try to see what the Rx8 tooth count is for the 4.4 they use.

 

I think it's an rx-8. Dude I bought it from fucked me over.