the same year, but what kind? Should I use synthetic oil for my 1992 Lexus? It's using a Camry engine, probably the same year, but what kind of oil should I be using, and how much should I be spending(expecting to pay)?
The approved oil viscosity of your year car is 5W-30. If the motor has no visible oil leaks it's perfectly all-right to switch to a full synthetic motor oil such as Mobil1. It's easy to find as Walmart stocks it on their automotive shelves in five quart plastic bottles. It costs $26.00 per five quart bottle and you could purchase it there and have a local Toyota dealer pull off the oil change. They don't care if you haul in your own oil. They will charge you approximately $21.00 for a basic oil change including a new Toyota oil filter made by Denso using your synthetic oil.
The plus side of Mobil1 5W-30 is it pours at -47 below 0 Farenheit. Regular 5W -30 stops pouring at temperatures below -35 below 0. It's to your advantage to allow the oil pump to force the greatest volume of oil to critical frictional surfaces quickly during cold starts. Speaking of cold starts, weather it be in Winter or Summer 80% of all engine wear occurs when you first hit the ignition switch.
Mobil1 has a fantastic detergent package to keep the inside of the motor clean as well as other additives for high temperature volatility and anti-wear properties.
Don't fall for the advise of using "thicker" high viscosity motor oil. It does not adsorb heat as well, it creates more drag on the oil pump sucking horsepower out of the motor, and does not pump as freely during cold starts.
If you'r intrested in seeing what the Joe Gibbs Race Team uses for oil viscosities go directly to Joe Gibbs Racing Oil. They use 0W for qualifying, 0W-20 during compition when restrictor plates are used and 5W-20 when they're able to unleash the full 875 horsepower unrestricted engines on specified race tracks.
The point is, thick old fashoned heavy weight (10W-40 - 10W-30 - 20W-50) multi-viscosity motor oil has no use these days in a motor that is in relatively good condition. Perhaps an old oil leaker or burner would benifit by using a stop gap band - aid. It's not the answer to a cause however.
how many miles has it done and what does the handbook say? High mileage engines need a thicker viscosity not necessarily synthetic. just change it every 10k along with filter.
If it hasn't had synthetic in it , I wouldn't use it now. All oils are better than years ago , just stick with a name brand and use the recommended weight (5w30) .