a few filter questions & Gear Oil

[Perez Oscar <PerezO@xxxxxxx>]

1. Are factory filters better than what you can find at the auto store?  

2. If so, why, and is this so for all Alfas?  If the answer is yes, where
can I get them for $5!

ALSO-- I don't want to start a long thread on this.. But..  any ideas on a
good gear oil for late model spiders.  Can I use the same oil on my Diff and
Transmission?-- I have some Redline 75W90 I haven't used yet.  any
suggestions appreciated.  

Oscar 
New to me 91 spider
Speedway, IN

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