Hello everyone, I can't tell if this is purely psychological or not but my 4.8 seems to not sound as good as it did just week or two ago. It doesn't seem to have the rumble anymore and when I gunned it through a tunnel it sounded really weak. Is this just me or is it the weather (75 degrees) or is the car (22,000 miles, '06 4.8is)?

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2006 BMW X5 4.8is Lemans Blue/Beige/Dark Maple
-Nav, Comfort Seats, Heated Steering Wheel,
Rear Airbags, AUX Input
2009 BMW M3 Space Grey/Black/Carbon
-all options