my 06 3.0 I think it loud in the cabin also... before I purchased it, I actually drove another to see if it was normal and it was.. 2 issues I have with these 3.0 engines is they are loud in the cabin, and oil consumption which also is normal for these engines. My Ford explorer with 165K miles doesn't consume a drop .... (exaggerating) but I don't get check engine oil between oil changes like on the X5. These cars look great, drive great, handle beautifully, but the reliability and quality of parts I'm not impressed.