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hello all i just baught a 1996 sts it has 122000 miles and need to do an oil change, i notticed the car used a bit of oil but not alot 1/2 quart for 3000 miles and i am thinking of switching it to castrol syntec 5w50? and thaughts on this? and does anyone know a good place to buy cheap zr tires? online even... thanks

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tirerack.com is a pretty good place to find tires (my personal choice is pirelli tires). As far as the oil goes alot of times switching to a synthetic will actually cause oil consumption to get worse (or leaks to appear).

I'm currently running 10w-30 Castrol GTX High Mileage in mine right now and so far no noticeable oil comsumption. The car is acutally running much better than it did on the Synthetic Blend 5w-30 oil I used last time (was not a high mileage blend). I wouldn't drift to far from the recommended 10w-30.

The Green's Machines

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5W-50 oil, even in synthetic, is way too thick for a Northstar. Use 10W-30. I've never used a drop of synthetic oil in my life, and my engine (with 152,000 miles currently) uses about a quart every 3000 miles. The GM spec is 1 quart every 1000 miles. Understand that the Northstar isn't your run of the mill small block Chevy. It uses some oil, by design. But that's also the reason it still runs like new when it's a couple hundred thousand miles old.

Use a quality 10W-30 oil of your choice and you'll be grand.

Jason(2001 STS, White Diamond)

"When you turn your car on...does it return the favor?"

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Not only is 5w-50 WAY too thick for a Northstar, even in Castrol's synthetic labeled bottle (it's actually a group III oil) it has way too many VII's (viscosity index improvers) which will break down in the ring grooves and stick them solid. This will throw your current excellent oil consumption right into the garbage can! Look in the owners manual, either in the glove box or online, and use exactly what it tells you in there.

PS, save your money, you don't need synthetic oil in this engine, nor is it recommended.

My current favorite for my '99 STS is 10W-30 Havoline. I do a complete oil change with filter for about $20.00. OH, and don't fill the crankcase to the FULL mark on the stick, unless the engine is HOT and on level ground at the time. I fill mine to the ADD mark only (about 6 quarts, give or take)

Never underestimate the amount of a persons greed.

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Some here are happy with a quart every 1200 miles, you are doing great. 10W30 is the way to go

Pre-1995 - DTC codes OBD1  >>

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