my gear box rear seal on my r32 rwd gtst i thought was leakin, but replacing it didnt help, well problem was the inner boot on the top of the box, it had a leak, and was dripping down out the back onto were the seal was and was spinning up and around my tunnel creating the impression it was the seal, its a common problem and a 20 dollar part from holden or nissan any rb box,
cheers brett