Hey all- so I have an 07 is250 with 224k on it. For the last year or so its made this extremely bizarre noise when I shut it off. Sounds like when you cast a fishing pole is the closest thing I can think of to explain it- like a zzzzzzzzz. I asked around and no one had a clue what it could be. Within the last month I have taken it to two master techs, both said the same thing. The timing chain is going. Besides this issue, the car is great and has been for the 5 years ive had it. Very minor fixes and very few of those. So my question is, it was always my understanding that the timing chain rarely goes before the motor. Is this likely to happen, is there any way to predict when or how soon, should I sell it and wash my hands of it before it does?? Any advice or input greatly appreciated!!!