One of the claims the oil companies make about using High Mileage oil is that over time, the clearances of engine parts becomes less, and you need a stronger/thicker shield between the moving parts, otherwise, premature wear will occur. Is that a load of bull? Any oil of the proper weight for the engine will protect from wear just as much as any other oil if used within the proper OCI right? The only thing High Mileage oil really does is swell the seals to help prevent leaks from what I’ve been told by some.
Regarding HM oil, is this really true?
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Originally Posted By: Mark72
One of the claims the oil companies make about using High Mileage oil is that over time, the clearances of engine parts becomes less, and you need a stronger/thicker shield between the moving parts, otherwise, premature wear will occur. Is that a load of bull?
Clearances become greater, not less. But it's true in theory. The only question is whether they become large enough to require a heavier or "tougher" oil. That's possible but not necessarily true.
Originally Posted By: Mark72
Any oil of the proper weight for the engine will protect from wear just as much as any other oil if used within the proper OCI right?
No. No matter how frequently you change it, the oil still has to be formulated correctly to match the engine's design, resist deposits and breakdown, etc. It's bad to have the wrong kind of oil even if you change it every thousand miles.
Originally Posted By: Mark72
The only thing High Mileage oil really does is swell the seals to help prevent leaks from what I’ve been told by some.
I'm sure there's more to it than that. But maybe not...
One of the claims the oil companies make about using High Mileage oil is that over time, the clearances of engine parts becomes less, and you need a stronger/thicker shield between the moving parts, otherwise, premature wear will occur. Is that a load of bull?
Clearances become greater, not less. But it's true in theory. The only question is whether they become large enough to require a heavier or "tougher" oil. That's possible but not necessarily true.
Originally Posted By: Mark72
Any oil of the proper weight for the engine will protect from wear just as much as any other oil if used within the proper OCI right?
No. No matter how frequently you change it, the oil still has to be formulated correctly to match the engine's design, resist deposits and breakdown, etc. It's bad to have the wrong kind of oil even if you change it every thousand miles.
Originally Posted By: Mark72
The only thing High Mileage oil really does is swell the seals to help prevent leaks from what I’ve been told by some.
I'm sure there's more to it than that. But maybe not...
Seal conditioners AND more anti-wear additives.
High Mileage oils are generally a bit thicker than 'regular' oil . They lean towards the thick side of the range. Not a huge difference, but in that direction.
They do have seal conditioners/swellers.
And more of the additives in normal engine oil.
Engines do indeed get 'looser' as they wear and age. Normally, this is a very very slow process.
Very roughly, in a modern engine, we can consider going up a grade after 150k+ or so.
If it is not burning excessive oil, and oil pressure is good, use the lighter initial oil.
They do have seal conditioners/swellers.
And more of the additives in normal engine oil.
Engines do indeed get 'looser' as they wear and age. Normally, this is a very very slow process.
Very roughly, in a modern engine, we can consider going up a grade after 150k+ or so.
If it is not burning excessive oil, and oil pressure is good, use the lighter initial oil.
Like was said as engines wear and the space between the metal parts where oil flows becomes larger and as it becomes larger oil pressure decreases. You can get oil pressure back up using a thicker oil like a High Mileage oil. That and High Mileage oils contain seal conditioners and extra anti wear additives.
Originally Posted By: FL_Rob
Seal conditioners AND more anti-wear additives.
I once partook in a Forum where they are of the belief that High Mileage oils "Condition" the seals by EATING AWAY at them! I cant see how or why people say that. They also like 20W-50 on there too, and I am inclined to believe them.
FL_Rob, I am in FL too.
Seal conditioners AND more anti-wear additives.
I once partook in a Forum where they are of the belief that High Mileage oils "Condition" the seals by EATING AWAY at them! I cant see how or why people say that. They also like 20W-50 on there too, and I am inclined to believe them.
FL_Rob, I am in FL too.
The SAE J300 spec for 30 wt. oil ranges from 9.3 centiStokes to 12.49 centiStokes @ 100°C. The High Mileage oils can be at the higher end of the allowable range.
The viscosity of the oil must suit the oil clearances in the machinery. If there is wear, then at some point thicker oil is required to prevent metal to metal contact. I don't think this happens at 75,000 miles or whatever the recommendation for High Mileage oil is at...nor probably not at 175,000 miles in the modern, well cared for engine.
The viscosity of the oil must suit the oil clearances in the machinery. If there is wear, then at some point thicker oil is required to prevent metal to metal contact. I don't think this happens at 75,000 miles or whatever the recommendation for High Mileage oil is at...nor probably not at 175,000 miles in the modern, well cared for engine.
What did we ever do before h/m oil? Did my 1980 f250 with 400k(when the odometer stopped working)no longer start? Use excessive oil? No.
'76 Olds cutlass supreme(two door of course)No.
'69 Firebird?
'91 wrangler?
'98 Astro 200k?
'94 f-150 (300l6)
current work van'93 G20 198k..My point is Im a little peeved when a company(ies) touts 75k or 90k as needing H/M oil.It seems they're feeding off the paranoia and worry of of motorists that dont drive newer cars.To each their own ,but I'm not buying it(duality implied).
'76 Olds cutlass supreme(two door of course)No.
'69 Firebird?
'91 wrangler?
'98 Astro 200k?
'94 f-150 (300l6)
current work van'93 G20 198k..My point is Im a little peeved when a company(ies) touts 75k or 90k as needing H/M oil.It seems they're feeding off the paranoia and worry of of motorists that dont drive newer cars.To each their own ,but I'm not buying it(duality implied).
Originally Posted By: FL_Rob
What did we ever do before h/m oil? Did my 1980 f250 with 400k(when the odometer stopped working)no longer start? Use excessive oil? No.
'76 Olds cutlass supreme(two door of course)No.
'69 Firebird?
'91 wrangler?
'98 Astro 200k?
'94 f-150 (300l6)
current work van'93 G20 198k..My point is Im a little peeved when a company(ies) touts 75k or 90k as needing H/M oil.It seems they're feeding off the paranoia and worry of of motorists that dont drive newer cars.To each their own ,but I'm not buying it(duality implied).
Timed out.I almost forgot '84 K20 (scottsdale trim... and for the younger crowd ,it's the equivalent of a modern 3500 4x4)it had 185K on it 8 years ago when an old neighbor BEGGED me to sell it to him.Just outta the blue I saw it last week on the road (it actually passed me) living now as a contractors work truck.I was shocked.
What did we ever do before h/m oil? Did my 1980 f250 with 400k(when the odometer stopped working)no longer start? Use excessive oil? No.
'76 Olds cutlass supreme(two door of course)No.
'69 Firebird?
'91 wrangler?
'98 Astro 200k?
'94 f-150 (300l6)
current work van'93 G20 198k..My point is Im a little peeved when a company(ies) touts 75k or 90k as needing H/M oil.It seems they're feeding off the paranoia and worry of of motorists that dont drive newer cars.To each their own ,but I'm not buying it(duality implied).
Timed out.I almost forgot '84 K20 (scottsdale trim... and for the younger crowd ,it's the equivalent of a modern 3500 4x4)it had 185K on it 8 years ago when an old neighbor BEGGED me to sell it to him.Just outta the blue I saw it last week on the road (it actually passed me) living now as a contractors work truck.I was shocked.
FL Rob-
Those cars you cited did not spec 5-20 originally, did they?
You are talking about a time when thicker oils were used. And they were thicker than High Mileage oils of now!
Those cars you cited did not spec 5-20 originally, did they?
You are talking about a time when thicker oils were used. And they were thicker than High Mileage oils of now!
Originally Posted By: FL_Rob
Originally Posted By: FL_Rob
What did we ever do before h/m oil? Did my 1980 f250 with 400k(when the odometer stopped working)no longer start? Use excessive oil? No.
'76 Olds cutlass supreme(two door of course)No.
'69 Firebird?
'91 wrangler?
'98 Astro 200k?
'94 f-150 (300l6)
current work van'93 G20 198k..My point is Im a little peeved when a company(ies) touts 75k or 90k as needing H/M oil.It seems they're feeding off the paranoia and worry of of motorists that dont drive newer cars.To each their own ,but I'm not buying it(duality implied).
Timed out.I almost forgot '84 K20 (scottsdale trim... and for the younger crowd ,it's the equivalent of a modern 3500 4x4)it had 185K on it 8 years ago when an old neighbor BEGGED me to sell it to him.Just outta the blue I saw it last week on the road (it actually passed me) living now as a contractors work truck.I was shocked.
Thats why i try to make posts to the effect that if you had car from an era where they did NOT spec 5W-20 or 5w30, using 5W-20 and or 5w30 in these cars is NOT a good idea.
Then people come in and say that "No car manufacturer EVER spec'd heavier than 10w30" but 10W-40 is the most common grade in the USA, and for Euro cars people have no issue putting 20W-50 in there even when they conclude 10W-40 is probably fine. Even aquariuscsm puts 20W-50 oil in his 1996 Twin Turbo Nissan Z. Bet ya it did NOT spec it. But it works FINE! Its synthetic too, but that does not really matter. Pennzoil conventional would work fir him too.
Same way Dr. Haas puts 10w30 in his Enzo which specs 10W-60, and same for a BMW M3 with the 10w30 in a 10W-60 car, even 5w30 one suggested. Two references.
Im sure if the car was to be operated for hours a day, the heavier Oil would be good.
Originally Posted By: FL_Rob
What did we ever do before h/m oil? Did my 1980 f250 with 400k(when the odometer stopped working)no longer start? Use excessive oil? No.
'76 Olds cutlass supreme(two door of course)No.
'69 Firebird?
'91 wrangler?
'98 Astro 200k?
'94 f-150 (300l6)
current work van'93 G20 198k..My point is Im a little peeved when a company(ies) touts 75k or 90k as needing H/M oil.It seems they're feeding off the paranoia and worry of of motorists that dont drive newer cars.To each their own ,but I'm not buying it(duality implied).
Timed out.I almost forgot '84 K20 (scottsdale trim... and for the younger crowd ,it's the equivalent of a modern 3500 4x4)it had 185K on it 8 years ago when an old neighbor BEGGED me to sell it to him.Just outta the blue I saw it last week on the road (it actually passed me) living now as a contractors work truck.I was shocked.
Thats why i try to make posts to the effect that if you had car from an era where they did NOT spec 5W-20 or 5w30, using 5W-20 and or 5w30 in these cars is NOT a good idea.
Then people come in and say that "No car manufacturer EVER spec'd heavier than 10w30" but 10W-40 is the most common grade in the USA, and for Euro cars people have no issue putting 20W-50 in there even when they conclude 10W-40 is probably fine. Even aquariuscsm puts 20W-50 oil in his 1996 Twin Turbo Nissan Z. Bet ya it did NOT spec it. But it works FINE! Its synthetic too, but that does not really matter. Pennzoil conventional would work fir him too.
Same way Dr. Haas puts 10w30 in his Enzo which specs 10W-60, and same for a BMW M3 with the 10w30 in a 10W-60 car, even 5w30 one suggested. Two references.
Im sure if the car was to be operated for hours a day, the heavier Oil would be good.
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