Good day!!

Well, if I had to guess, it would be the fact that the air is indeed cooler and thinner, but the motor is pumping fluids faster than at the lower RPM's... It is working harder, but for the 4.6is, climbing hills is barely breaking a sweat for it...

There is an oil cooler that has a thermostat on the N62 motors, but I'm honestly not sure about our 4.6L M62TU...

Cheers!!!

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2001 E53 X5 4.4i (03-07-2001 build date) White exterior / hellbeige interior (6MT swap vehicle - Manny)
2002 E53 X5 4.6is (12-20-2001 build date) Imola Red exterior / M-texture interior (Red)
2003 E53 X5 4.4i (06-26-2003 build date) Silver exterior / Black interior (Silvester II)
2008 Mini Cooper S ragtop (04-17-2008 build date) Dark Silver exterior / Gray interior ( Topless)
BMWCCA member (#4745)