Change the rod bearings and cross your fingers!

Someone (not me) came home from a 40mile drive and informed me that the car sounded like a sewing machine the whole way home.

Not enough oil to pump up the lifters.

The engine had 60,000 miles on it.

Put a bottle of slick 50 in and the rest with oil.

For the next 100,000 miles it had a deep thunk, (rod knock)

Only stopped driving the car when I couldn't get the auto trans to shift into druve anymore, reverse was fine.

Moral to the story...

All you have to loose is time and a few bucks.