I have to agree. I just did this on my 4.6....you're better off spending a little extra and doing the all of the guides, the chain(s), and tensioners while you're in there. Cheap insurance if you ask me. I also had a failing bank 2 vanos that I also replaced. Holy crap, I couldnt believe how much power I'd lost along the way.

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2011 Sapphire Black X5D
Burger Tuning JBD
Lux H8 V4 Angel Eye LEDs