Hi everyone,

This is my first X5 and first V8 BMW. It is a 2002 4.4 with about 75k miles. I bought it a few months back and have put approximately 5k miles on it. I was a own owner dealer serviced unit. Previous to purchasing I had it inspected at Erhard BMW in Michigan and it passed with flying colours. I changed the oil about 1000k ago with castrol syn as per BMW recommendation. Ever since I've noticed a very slight knock. It seems to be coming from the bottom end and not a lifter type noise. It only occurs after the vehicle warms up. Only a trained ear would hear it. I am just wondering if this is commonplace as i heard early 4.4's in the E39's had a similar noise. Any input would be great.

thanks

is it a tock tock tock tock noise?

Are you running a minimum 91 octane?

I have 2007 X5 (E70), I used to have similar knocking sound, but since I started fueling up at Shell, the problem disappeared. BMW recommends Shell and Chevron. Try good quality gas and see what happens.

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