Loud rear exhaust fan

[Waltz]

Hello to you all.

I don't know if i'm posting this thread in the right spot but if not i apologise for that.

I built my system around 8 months back and installed 5 fans: 1 front intake, 1 bottom intake, 2 on the cpu cooler on push-pull and 1 rear exhaust fan. The fans are cooler master sickleflow 120mm and they're all actually pretty quite except for the rear fan. It almost sounds like a get engine on full throttle. I've connected the 2 cpu fans on the 2 cpu fan headers, the front intake is on molex and the rear and bottom are connected in chasis fan headers and they're all tuned to run on the lowest speeds possible.

Is there any advice from you guys to my problem? Thank you all in advance

 

[i7Baby]

Replace it. Or use a resistor to lower its speed - http://www.newegg.com/Product/Product.aspx?Item=9SIA4SR1PN3307

 

[Waltz]

Thanks for your quick answer but other than that can I try anything else?

 

[i7Baby]

Blow dust out with compressed air and put a drop of WD40 on the fan bearing.

 

[Waltz]

Blow dust out with compressed air and put a drop of WD40 on the fan bearing.

Ok thanks i'm gonna try that out