don't think a shift kit would void your warranty if the Interceptor doesn't, and I also don't think an LSD would, because they wouldn't know it was one, and LSD looks exactly the same as the stock diff. and in 3 years the Interceptor may have already ruined your tranny. I think if you took 2 hours of your time to put in a shift kit, you would be much more pleased. Just my opinion though. Without a shift kit the Interceptor is much needed though, otherwise the shifts are really wimpy and mushy.