As Dutch pointed out...
I've had a head gasket leak reported via oil analysis twice in the last 30 years, but it allowed repairs to be done
before it killed the engine, antifreeze doesn't do the main bearings much good.... messes them up in short order.
I've also been thinking about a remote filter on the 4Runner...to run a 2 qt Ford Truck filter.
I run 20 to 25,000 mile drain intervals on that vehicle already....
and to answer Pete's question... you don't have to get it done every oil change....
anyone ever seen that old article from Popular Mechanics from back in the 70s, where an
engineer at Ford, ran a Lincoln he bought from the company after it had been used for some testing.
he ran the car 100,000 miles ( back then) with no oil changes, using Mobil ONE back when it was only
in 5 W 20... changed the filter every 5K.. and added as needed. then tore the engine down at 100K..
it showed little wear for an engine with a 100K on it...
the article is still floating around the internet.
