year but... I bought mine through SZ, shipped my diff to them through UPS and paid around $120, had the gears installed by the people that SZ uses and had it shipped back ready for install. All in all, I think the total cost was around $1200. I did the removal and reinstall with a friend so there was no labor cost. I followed the break-in procedure but still had a little whine at 60 and a more dreadful whine at 70. I didn't care either way considering I primarily drove the car w/ the tops off. Your typical street driving you can barely notice the whine.