30 psi was too low, but where in the US are you able to drive with 4/5 passengers and a full load of luggage, at over 100 mph for any extended periods? 42 psi in the rear seems excessive. I can see 35 psi in the fronts; I never went above that for the rears when fully loaded. Most of the time I used 32 front and rear.

You won't have proved any connection with tire pressure until you put them up, and then back down, through a few cycles, and see if the noise comes and goes with the pressure increases.

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2007 X3 3.0si, 6 MT, Premium, White

Retired:
2008 535i, 6 MT, M Sport, Premium, Space Grey
2003 X5 3.0 Steptronic, Premium, Titanium Silver
2002 325xi 5 MT, Steel Grey
2004 Z4 3.0 Premium, Sport, SMG, Maldives Blue