I have a 2005 g35 and with 5 minutes of driving the backup fan turns on and its super loud, someone told me it could be a relay fuse but im not sure, the gauge dosent show it overheating but wen the fan does come on its super loud.

 

Our fans are loud, just something you'll get used to. Doesn't sound like anything's wrong with your car to me.

 

A/C fan sure is loud when it is on the higher fan settings! But the air coming out of the vents is ice cold!

 

OP, how are your coolant levels? The fans could be the only thing keeping it from overheating if your radiator isn't 100% full.

You could get a KOYO aluminum radiator. Haha my fans never come on even with ac on and sitting for 6 mins in a drive through.