Local mechanic made a list of what according to him needs done to my car. One of which was replacing spool valve assembly. I have oil leak all over the place. Question is does this part ever need to be replaced? Im seeing where alot of guys just change the gasket or seal thats on it. Just curious if theres ever a reason to replace thewhole thing?

 

95% of the time it's gaskets/seals that leak oil.
Unless the housing itself is cracked, which I doubt, I would change just the gasket (with integrated filter screen).