Oil Change twice yearly? With Low Mileage

this is a quick read...one interesting point is that a hotter climate will break down an oils properties more quickly than a cooler one.

oil over time

"As an oil breaks down it combines with combustion chamber residue from blowby gasses to form sludge. High detergent oils dissolve this sludge and hold it in suspension. In addition, as an engine wears small pieces of metal, rubber, and plastic end up in the bottom of the oil pan. Believe it or not, the "granny car" which is "short tripped" will have a lot more acids (condensed from blowby gasses) mixed with the oil than a car which is driven every day! I rebuilt one engine with a thrown rod: (old lady, once a week to the store 3 miles away) The rod bearing had been eaten away by acid deposits!!! Ony 40,000 miles on that motor! Thus on low mileage cars I recommend changing the oil every 6 months, no matter how many miles on them!"