Automobile(s): 1984 Buick Electra Estate Wagon aka Country Cadillac
Re: repost: Oil pressure light
My 84 Electra wagon 307 has about 3 loose rods. I found that out when I did the valve cover gaskets. Who knows how long it was like that. Runs like a watch, even ticks like one too. I had it since Feb. It has taken me on 50 mile trips a few times.
But my car also has the low oil pressure problem, it only happens after a good run on the interstate. When I stop I got to put it in neutral or it will stall. I can do city driving all day and it will not come on.
Run the thickest oil you can find. I would start off with no less than 15W40. Run it year round unless you live in Northern Alaska or Minnesota.... If it regularly gets below -5F, then during those months change to 5W30, then swap it out ASAP when it warms up. But honestly, 15W40 is likley fine. Semi's use it year round.
In warmer months, run 2 bottles of STP oil treatment in place of 1 qt really helps the low rpm oil pressure. In winter months 1 bottle. It will help a lot in the low rpm oil pressure.