That would be a temporary fix if anything. And sometimes those additives will coat your internals with crud and make it a more pricey fix when u do fix it. You need to either rebuild it or do an engine swap
If it's only a slight leak and your sure it's the main I'd just leave it until the next time you do your clutch and throw-out bearing. T5 can be carried around by one guy. AOD you better get some help :yup: it's a 5 minute job pick the old one out and tap in a new one. I'd make sure it isn't the valve covers running down the bellhousing first IMO. Same thing happened to a friend of mine.
A forum community dedicated to Ford Mustang owners and enthusiasts. Come join the discussion about performance, builds, modifications, reviews, engine swaps, classifieds, troubleshooting, maintenance, and more!