In Australia, I am having great difficulty finding a 10W-40 mineral (non synthetic) engine oil. 10W40 is the recommended viscosity for my car, and a synthetic would do more damage than good due to the motors age. They don't sell Castrol GTX 10w40 and Shell 10w40 is semi synthetic.
Looking for 10w40 mineral oil
- Thread starter Jabbo
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Why do you think that synthetic would do damage?
I've got an 84 year old car, I don't think synthetic would "damage" anything in that engine...but given how that car is driven, synthetic is a waste of money...
I've got an 84 year old car, I don't think synthetic would "damage" anything in that engine...but given how that car is driven, synthetic is a waste of money...
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Some old wive's tales never die...
Originally Posted By: BikeWhisperer
Some old wive's tales never die...
I know but it gets a bit ridiculous after a while. If synthetic did more harm than good at advanced mileage then I'm screwed.
To answer the OP, just find something that is xW-40 and go for it. I'm guessing that a 15W-40 of some brand is readily available. The first number with the "W" is irrelevant in for your situation.
Some old wive's tales never die...
I know but it gets a bit ridiculous after a while. If synthetic did more harm than good at advanced mileage then I'm screwed.
To answer the OP, just find something that is xW-40 and go for it. I'm guessing that a 15W-40 of some brand is readily available. The first number with the "W" is irrelevant in for your situation.
I'll send you a case of Chevron Supreme 10W-40; how's that ?
The reason behind my view towards synthetic is because I've seen after some people switch to synthetic, their seals start to leak including valve stem seals, which means burning oil. In old motors, gunk on the seals may well be whats holding them together and sealing it. Synthetic oils are great at removing sludge, so when it removes the gunk from around the seals, the seals may start to leak.
Just grab some Castrol GTX 15W-40, it's a full mineral, quality oil that you can find everywhere and often at a good price.
The 10W Vs 15W is a sub-zero winter rating for cold starts. It isn't an oil "weight". Given you live in QLD, it never gets cold enough for the difference to show. Without looking at tables, it's something like -20 C to see a difference.
You just need a "40 weight" oil, any xW-40 will do in Oz.
The 10W Vs 15W is a sub-zero winter rating for cold starts. It isn't an oil "weight". Given you live in QLD, it never gets cold enough for the difference to show. Without looking at tables, it's something like -20 C to see a difference.
You just need a "40 weight" oil, any xW-40 will do in Oz.
40 some years ago pure synthetics (Group 4 and 5) were not easy on old seals. But that has not been the case for decades.
Today's conventional oils clean as well as most synthetics. If you're worried about seals, use a high mileage oil. If the seals still leak then your engine needs work...it's not the oil's fault.
Today's conventional oils clean as well as most synthetics. If you're worried about seals, use a high mileage oil. If the seals still leak then your engine needs work...it's not the oil's fault.
Originally Posted By: SR5
Just grab some Castrol GTX 15W-40, it's a full mineral, quality oil that you can find everywhere and often at a good price.
The 10W Vs 15W is a sub-zero winter rating for cold starts. It isn't an oil "weight". Given you live in QLD, it never gets cold enough for the difference to show. Without looking at tables, it's something like -20 C to see a difference.
You just need a "40 weight" oil, any xW-40 will do in Oz.
Exactly, just use a 15w-40 HDEO dual rated oil.
Just grab some Castrol GTX 15W-40, it's a full mineral, quality oil that you can find everywhere and often at a good price.
The 10W Vs 15W is a sub-zero winter rating for cold starts. It isn't an oil "weight". Given you live in QLD, it never gets cold enough for the difference to show. Without looking at tables, it's something like -20 C to see a difference.
You just need a "40 weight" oil, any xW-40 will do in Oz.
Exactly, just use a 15w-40 HDEO dual rated oil.
+1 on HDEO for high mileage motors. Good choice, been doing it for decades
Or actual High Mileage oil with seal conditioner...
Or actual High Mileage oil with seal conditioner...
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