This is the Trac Loc I received from my neighbor, Story is, He got it from the parts bin at the dealership. Tried to place it in a 8.8 he was building for his ranger. Bolt holes would not line up, figured it was for a 7.5. Told me he found out it was from a 99 Ranger with 7.5 LSD. I don't want to dought his info, But during my hunt for new clutches, I got worried it could be from a 28 spline 8.8, or the 28 spline 7.5. I don't know, and part numbers on case lead me no where.

 

After comparing pictures of the 7.5 and 8.8's online, It seems like this is a 7.5 unit, but one person to confirm that, and i'll order the clutch kit and F150 spring.

 

I can't guarantee it but I did a little looking around as well and everything I see makes me believe it's for a 7.5".