Extend OCI with STP?

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Ohio
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As mentioned in previous threads I recently changed my oil and this time used 15oz blue bottle STP. My car's OLM seems to kick on the "change oil" light around 5,000 miles but I was wondering if it's possible to extend out this OCI because of the additives from the STP I imagine it'll last a bit longer? Just curious. Thanks
 
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St. Charles County, Missouri
STP came in handy for me when the ten weight winter oil was in my '53 Mercury (in the mid sixties) and it got warm in the spring. You raised the weight of your oil during the winter--in Ohio, not much else. Don't think it would do a thing to extend your OCI.
 
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Wet side WA
Originally Posted by cwilliamsws6
As mentioned in previous threads I recently changed my oil and this time used 15oz blue bottle STP. My car's OLM seems to kick on the "change oil" light around 5,000 miles but I was wondering if it's possible to extend out this OCI because of the additives from the STP I imagine it'll last a bit longer? Just curious. Thanks
A UOA can help you with this decision.
 
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Southeast Texas
Originally Posted by cwilliamsws6
but I was wondering if it's possible to extend out this OCI because of the additives from the STP I imagine it'll last a bit longer?
I have wondered the same thing. If additives are boosted a bit, I think the OC can be extended. Of course someone will point out that STP does not make oil new again, or remove contaminates, but thats not the point. I think a good additive would buy you some time. It should mitigate some depletion of the oils additive package.
 
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Ontario, Canada
Originally Posted by JohnnyJohnson
Originally Posted by cwilliamsws6
As mentioned in previous threads I recently changed my oil and this time used 15oz blue bottle STP. My car's OLM seems to kick on the "change oil" light around 5,000 miles but I was wondering if it's possible to extend out this OCI because of the additives from the STP I imagine it'll last a bit longer? Just curious. Thanks
A UOA can help you with this decision.
A UOA likely costs more than just changing the oil in this case. OP: STP isn't turning your conventional vanilla sauce into M1 EP or AMSOIL.
 
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Upstate NY
STP will most likely reduce the OCI you should run. People used STP to thicken oil to pass emissions tests 20 or 30 years ago. Use high quality oil and forget additives. STP = Studebaker Testing Products
 
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1,414
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South Carolina
STP is just a thick bottle of OCP VII with a weak (and diluted) add pack in a group I carrier. It's pretty much the same as Lucas Oil Stabilizer except Lucas contains no add pack at all. It WILL shorten the OCI as the anti-oxidants, detergents, dispersants, and anti-wear additives in your oil will be diluted by it.
 
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NH
Is your OLM nothing more than an idiot light? The two in my Toyota's are programmed to come on just prior to the 5k mark. That is because they "need" tire rotations every 5k, with oil changes every other. Completely miles based. [Which works fine by me, for the record.] I tend to have low opinions of additives. If they did something, they'd be in the oil already. Maybe they are, but in the high dollar oils. Who knows. As a last ditch effort to keep a poorly running engine going, ok no harm no foul. Maybe in really big engines with gallons of oil, maybe an additive makes sense... but that wouldn't apply to a passenger car with what, 4 or 5 quarts of oil?
 
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Meh. STP might help? It can't really hurt I suppose. A good modern day synthetic (Mobil 1, Amsoil, etc) will last. Many are guaranteeing a one year OCI or up to 25,000 miles with use in certain applications. I'm not a huge fan of additives. I figure the engineers at the companies know a wee bit more than I do. FWIW I do Amsoil signature once a year in all of my stuff regardless of mileage.
 
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Katy, Republic of Texas
All the blue bottle does is add some ZDDP (which could be argued that you do not need for that vehicle) and thickens the oil, it does nothing to extend the change interval. It really does nothing to help, and as said above, it may hurt by diluting the actual additives in the oil. I would change it now and then just use oil in the future. If you want to extend the interval, use a quality synthetic, not HK conventional (which there is nothing wrong with for a standard OCI) and STP. Depending on your driving conditions, HK synthetic would probably be fine for a 7500 mile interval (but a UOA will be the only way to know for sure).
 
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Originally Posted by blupupher
All the blue bottle does is add some ZDDP (which could be argued that you do not need for that vehicle) and thickens the oil, it does nothing to extend the change interval. It really does nothing to help, and as said above, it may hurt by diluting the actual additives in the oil. I would change it now and then just use oil in the future. If you want to extend the interval, use a quality synthetic, not HK conventional (which there is nothing wrong with for a standard OCI) and STP. Depending on your driving conditions, HK synthetic would probably be fine for a 7500 mile interval (but a UOA will be the only way to know for sure).
The amount of ZDDP in STP is <600 ppm Zn and <500 ppm P so it actually dilutes the ZDDP concentration in your oil. It's another example of deceptive marketing where they say "contains anti-wear additive ZDDP" but careful not to say how much.
 
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