How long of an OCI should I shoot for?

[55Test]

I 'spose I shoulda asked this when I first poured the golden GC in my car. My car is a 96 Sunfire, 2.2 with the 5 speed. Current mileage on the car is 160000 miles, but the engine was changed at one point a few years ago so I have no idea how many miles are on it. It runs pretty good, but it has an awful lot of what I believe is piston slap when it's cold, it mostly goes away once it's warmed up but if you listen closely you can still hear it. It's getting pretty near EPA fuel mileage estimates, I usually get 450 miles or so out of a full tank. The CEL comes on and goes off randomly, I don't believe it's anything serious though. Now, on to my main question. How long of an OCI should I go for? I'm using gold GC, batch M0533xx and a Carquest premium filter. I was going to change it at 6500 miles, I've got about 3000 miles left to go right now. I don't want to do a UOA, don't feel like spending the money on one. The car has used 1 quart of oil so far. I don't want to change the oil too soon, but I don't want to go too long either. What should I do?

 

[JAG]

Use maintenance doses of Auto-RX along with GC and see if consumption drops or fuel economy rises. If it does you can run longer OCI due to less blow-by contaminants getting into the oil and shortening its life. 6500 mi. with GC is fine with this engine's current condition but could be much longer if it starts running more cleanly. Or of course, you could do a full Auto-RX treatment but I figured you wouldn't be into that due to the hassle.