[THEFERMANATOR]

Originally Posted by smokeonthewater

I would NEVER use atf in a trim system... I have had to repair a few that had atf and some water in them and when atf mixes w water it becomes the nastiest goop ever... a true nightmare to clean out.... top it off and find the leak... hint... it's most likely the seal on the cylinder or if it has a hose that is another possibility

Last I checked ATF was the same stuff except dyed red and had friction modifiers in it that trim fluid doesn't have. You could also substitute power steering fluid if you're in a pinch.