Cutting right to the question: Conventional Oil or Synthetic Oil in a used engine of unknown history?
Background discussion information: is there anything to the anecdotally tale of not using synthetic oil in a higher mileage engine that has only been run with conventional oil?
My son has a 2008 V6 Mustang with the 4.0 engine. 115k on the odometer. We have zero information on what type of oil has been used in the engine by previous owners. Should we go Synthetic?
More possible information, I changed the oil in my 2007 Nissan Armada (198k miles) with synthetic and it immediately developed a huge gusher of an oil leak. Could be coincidence but it could be something too. Leaking about a quart every 800 miles.
What do you guys recommend?
My layman's terms...
Synthetic is "thinner" which is good for getting some oil everywhere but, it is common for synthetic to therefore leak through older gaskets.
Conventional oil back into the Armada and I think you will find that the leak will stop.
So, what do do with that relatively new Armada oil???
Capture it and put it in the Mustang (if the viscosity is correct)..look for leaking.
My understanding is that there is almost no actual conventional oil out there. There are some guidelines on what can be called "synthetic" or "full synthetic " but pretty much everything is synthetic blend at this point; and none of it's bad.
I use AmsOil in everything I own, literally down to the lawnmower. All of my stuff is well used when I take possession of it. Never any spontaneous oil leaks or any thing else negative.
