oil rod ?

Just use a light machine oil. WD40 if you have it in your region will also work.

I don't think WD40 should be used as a lubricant.

There is a brand here in the states called 3-IN-ONE. That's what I used. It's good for guns and any other light oil needs.

that's ok ? :

http://wd40specialist.com/products/silicone-lubricant/

efes, that would be fine. it's actually the exact same stuff I use for my screws and what not.

Dubbsd, that grease would also be a good choice. I tend to avoid using greases just because they leave a layer that dust and such can stick to and I tend to have a fairly dirty shop. The spray leaves a film that's a little less tacky from my experience.

If it was heavier weight, I would definitely go grease over spray, though.

I would avoid the sprays especially in the the closed systems, because if the oil gets on the print bed, the filament won't stick. Grease will stay together, be much less likely to get on the print bed, and is about the same price. But like TheBaron said, dust can get into the greases which means that you'll have to replace the grease every so often, depending upon your environment.