Toyota 3.4 engine? Right now, I have 207,500 on my 1998 4Runner's 3.4. Since I purchased it with 143k about two years ago, it has seen four OCI's of Redline and four SSO. The thing runs like it is new. Never a ping or a knock and smooth as [censored]. Is it possible to get 500k out of this engine? What do you guys think?