After searching and reading extensivly I am trying to resolve my wickid 2-3 and 3-4 shift flare. My initial check of the vacuum pot on the drivers side of the trans reveals a slow leak.

When pumped up to 15 hg it will zero out in about 12-15 sec so I know its not as new as it leaks ~1 hg/sec. Im asking beacuse I have read that a slow leak like this (if it is indeed considered slow) is not ideal but still servicable, I have also read if it does not hold vacuum its garbage and should be replaced before further adjustments and trouble shooting are performed? Which is true and if replace what do I need to know to get another (besides trans #)?

Thanks. I want to resolve this before I pull out the hyd psi gauge and set internal psi.

87 300SDL