Fan suddenly very noisy

[VanZan]

Had my T420 a few years with no problems. Now when I start the laptop and whenever the fan needs to work it sounds like an engine inside. No other problems using the machine. There's no slowdown in performance. I've just tried using compressed air on the fan and the vents but it hasn't helped.

Would it need oil or something like that? Or a complete replacement?

Thank you for any help!

[RealBlackStuff]

You need to take the fan apart to fully clean the blades and the housing, and then try to oil the fan itself.
Use sewing machine oil or similar.
But it might be gone too far already after so many years.
OR:
Check ebay.ie for lenovo t420 fan (NOT the T420s).
If you are handy, you can replace just the fan or else the whole unit.
There are 2 types, for integrated GPU (04W0407/04W0409) and for discrete GPU (04W0408/04W0410).

[VanZan]

Ah OK looks like I've a bit of work to do so. Yeah mine has the integrated graphics. Thanks.