Fantastic roof vent has become very noisy. Is there anything i can do to service it? (2 Viewers)

[MaidinDevon]

I am not experienced at DIY, bur this becoming do noisy when using it. Does it need a clean, perhaps.
I imagine it's original to the van, snd I haven't done anything in 5 years, it's pretty grubby.

 

[1967bowesj]

Put a picture up

 

[MaidinDevon]