Is high mileage synthetic oil really worth it?

I've not had an improvement using it.
Going back to regular syn.
Just as well off using a good syn oil and changing it on time
 
Here’s a question. Since the esters cause the seals to swell; would switching back to regular synthetic cause the seals to shrink and then leak?
 
Hi,
My 2017 Hyundai Elantra Value Edition just turned over to 75,000 miles. The car has been flawless and I still get 36MPG traveling in on the roads in central NJ, NOT even highway driving. I just purchased Pennzoil 5W-20 full synthetic for high mileage cars over 75,000 miles. The price is the same as the standard full synthetic and I was just wondering if the high mileage version can really be beneficial to use, or just stick with the regular full synthetic?
Thanks
Michael in Central NJ
It’s worth it when it’s on clearance like at TSC stores 🙊🙊
 
It is cheaper than regular so why not? I think it is time as my van crossed 200k miles.

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high milage oils is a most mysterious topic. Especially when they say it can be used in new cars, and often times cost the same as regular oil. Question remains, why not just make it standard in all oils?
 
I don’t “get” the HM oil in a premium synthetic format. The entire purpose of premium synthetic oils is to assure that as your vehicle achieves high miles, the engine is in excellent shape as if it were new.

And to the extent your engine is NOT clean inside or has leaking, it’s probably in an older vehicle where using a premium oil is probably less economical than a cheaper HM oil on shorter OCIs.

I suspect if it wasn’t for Red Jug Valvoline creating this arbritrary “high mileage” category with a niche product, these oils wouldn’t exist.


There’s also the tacit “in warranty” vs “not in warranty” oil distinction. I’ve seen people posit that a high mileage oil isn’t “watered down” to meet warranty needs (i.e. presumable a weaker add pack). I also don’t get that approach. If you believe your warranty-complying oil to inferior, why not just choose the better oil?
 
Because it has no added cost to them, and many of them say its OK to use it in new car. They should just stop this and make one premium oil
That’s never going to happen, especially with Mobil 1, as they love having many different versions of their oils. Too many, in my opinion, but they know what they’re doing since they are very likely the number one seller of oil in the world (at least off the shelf oils that is)
 
I don’t “get” the HM oil in a premium synthetic format. The entire purpose of premium synthetic oils is to assure that as your vehicle achieves high miles, the engine is in excellent shape as if it were new.

And to the extent your engine is NOT clean inside or has leaking, it’s probably in an older vehicle where using a premium oil is probably less economical than a cheaper HM oil on shorter OCIs.

I suspect if it wasn’t for Red Jug Valvoline creating this arbritrary “high mileage” category with a niche product, these oils wouldn’t exist.


There’s also the tacit “in warranty” vs “not in warranty” oil distinction. I’ve seen people posit that a high mileage oil isn’t “watered down” to meet warranty needs (i.e. presumable a weaker add pack). I also don’t get that approach. If you believe your warranty-complying oil to inferior, why not just choose the better oil?
The point is a little bit of an increase in seal conditioning to compensate for aging seals. You can achieve high miles through a premium oil but that doesn't eliminate seals from aging over time.
 
The point is a little bit of an increase in seal conditioning to compensate for aging seals. You can achieve high miles through a premium oil but that doesn't eliminate seals from aging over time.
That’s the theory at least. In practice, non-hm oils also have seal conditioning, just perhaps less of it.

I submit than an engine run it’s entire life in a premium non-hm oil will never need an hm oil.
 
That’s the theory at least. In practice, non-hm oils also have seal conditioning, just perhaps less of it.

I submit than an engine run it’s entire life in a premium non-hm oil will never need an hm oil.
What you do define as premium?
 
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