I think my pulleys have gone bad because there is very loud squeaking at start-up for a little while and then it goes away. I recently had put in brand new belts (I think they may have been Nissan though...).

Anyways, is it worth getting OEM pulleys or is aftermarket worth it?

By the way, does anyone possibly know the part numbers for these two tension pulleys for a 2003 Infiniti G35 Sedan?

Lastly, do you guys think that I might as well replace the belts too (these were replaced about 6 months ago or so) or do you think they should be fine. I'm not sure if it is true, but I've read online that bad pulleys can actually make the belts go bad.

Thanks