[CREWZIN]

Apparently your GF's GT had the oil usage problem from the factory. That's probably why it was sold or traded in. It could have happened later, but I doubt it. Parts for the assembly line come from a 1000 different manufacturers and bad ones do wind up being used. I had a Chevy Monza (back before your time) that made noise in the high range of each gear. Took it back for a check and before I knew it, they had the engine in pieces and found that one of the pistons was slapping around because of a bad bore in the cylinder head. Got a new short block from that episode. It was practically a brand new car and I had to live with a re-built engine for the next few years. Luckaly nothing ever happened after that for over 100,000 miles. Be thankful you kept checking the oil and caught the problem while it was still under warranty, as many owners would just keep driving till the engine seized from lack of oil.