So before my girlfriend and I started dating she bought a car...in the worst way possible...found it on craigslist, didn't test drive it, and paid for it because it was "cute". She has had it for a little of over a year now. This beast is at the end of it's life.
This past spring we found out the cooling fans weren't working because it overheated going up a mountain. I went to get her, filled the coolant back up, and followed her home. Mechanic fixed the cooling fan problem afterwards.
Since then the car seems to be eating oil (no apparent leaks though). I guessing a seal somewhere got cooked. At start up there is a big blue cloud and it continues until the engine warms up. After that no smoke even when the transmission shifts (I watched following her). It is burning enough oil that I've stopped changing it. I change the filter every 5k (cheapest available) and top her off once a week with the cheapest 5w-30 I can find at either the gas station or the Rural King. Still the amount being burned is ridiculous and once her new job starts paying we're going to get her into something else.
We have decided to keep the bug until it dies (as a 3rd "if one of the others is in the shop" vehicle) and then turn it into lawn art afterwards (thinking hood open and climbing roses).
What oil would you all suggest to maybe cut down on the burning and keep her going as long as possible?
Locally the thickest oils available are straight 30wt and 20w50, both "Warren" brand, both VERY cheap.
Engine rebuild/replacement is not an option. There is A LOT of other things wrong with the vehicle and it isn't worth actually fixing.