I knew I wasn't in Kansas anymore today when I cracked open my differential cover. I was surprised to see the little bugger missing. I'm used to my 88's 8.8 differential I guess. So why no spring? I was also hoping that I'd be able to use the new pinion shaft bolt I have from the truck 8.8 I recently set in my Mustangs differential...I had no idea the differential in my truck was 9.75. Can you rebuild the clutches like an 8.8? New experience.