1. Jack up rear of the Z
2. Place jack stand in factory locations
3. Remove rear diff cover
4. Check for LSD
5. Replace cover
6. Lower Z
Or, you could just read Red-Zed's post.
Don't mind me. I just have LSD envy.
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Rain, snow, sleet, hail: 2009 Mazda 3 sGT HB
Everything else: 2009 370z, PW Touring 6MT