Can anyone recommend a product that might mitigate a valve leak at the back of the engine and another on the oil pan? My mechanic, an honest conservative type, said the repair might not be worth it since the tranny has to be pulled to complete it. Is there any type of stop leak product that might help? Or do I just buy extra oil and keep the level up?
No. There are no additives that will stop valve cover/oil pan gasket leaks. These additives are formulated to stop oil leaks at the engine seals. So, you’ll have to keep an eye on the engine oil level if you don’t want to replace the gaskets.
Change the valve cover gasket. It’s very easy and super prone to leak. I’ve had 4 jeep inline 6 motors and I’ve changed them all and not one rear main seal. The oil leaks down and looks like a pan gasket/rear main. It’s fools a lot of people.