I recently switched to HM oils in my 97 Civic. One change of Castol GTX HM and now on to Mobil 1 HM. Finishing up the M1 oci shortly. In all about ~ 10k on HM oils, 155k total on the car. Car is in great mechanical condition with no leaks or consumption. I started using HMs simply to help the seals out given that is 18 years old surviving 10 degree winters and 100 degree summers here in Kansas. I'm starting to second guess my need for them though and would like to move back to standard syns &/or dinos provided I haven't made my seals dependent on the added conditioners/swellers. Is this safe to do?
Moving away from HM oil: safe to do?
- Thread starter zuluplus30
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Probably but I would at least use one qt of a hm oil to keep the swelling effect in check.
Yes it is safe. People do it all the time.
I recently moved from HM to conventional and my car consumes zero oil. And I say this with a 6,000 mi OCI on plain conventional oil under my belt since moving away from HM.
I recently moved from HM to conventional and my car consumes zero oil. And I say this with a 6,000 mi OCI on plain conventional oil under my belt since moving away from HM.
You will be fine. Even if your car naturally leaks its not like the engine will notice its not high mileage the seals will still be in good condition.
Go for it. I switched to high mileage oil in my Acura to stop a leak and then switched back to synthetic for the next 2 oil changes and the leak never returned. Heck, if it starts to leak, just switch back.
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ALL oils have some amount of seal conditioner. All you are doing is wasting your time and money. You don't utilize the oil long enough for any oil to do much of anything.
I'll play the Devil's advocate here.... I wouldn't, I'd go with a high quality full synthetic like maxlife. I owned a 99 Protege. I used high mileage oil on it for a couple of years then sold the car to a friend. This buddy of mine did not use high mileage oil and after a year the car had a catastrophic seal failure. He could only drive it for about a half an hour before he went from to full oil to nothing. Now, I realize this could be purely coincidental, I have no proof what so ever that going away from a high mileage oil caused this, but it sure made me wonder. You could go with regular oil plus some redline ester oil or perhaps lubegard biotech to ensure that your seals stay healthy and conditioned...
Stick with HM oil once you start. Seals swell a little more using HM oil, and you want to keep them that way.
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With no leaks and no consumption, why did you switch in the first place? Just because a vehicle surpasses 75K on the odometer, doesn't mean you need to switch to seal conditioners.
What's the old expression?..... don't try to fix what isn't broke.
What's the old expression?..... don't try to fix what isn't broke.
What is causing you to make the switch back? Is it cost?
"Regular oil" vs. HM oils are either the same or similar in price. You might be paying a few $$$ more, but that's it. IIRC, M1's normal stuff vs. the HM formulation is actually the same price at WM. I would keep doing what your'e doing.
You can always switch back and see if consumption increases a bit without a HM oil and go from there.
"Regular oil" vs. HM oils are either the same or similar in price. You might be paying a few $$$ more, but that's it. IIRC, M1's normal stuff vs. the HM formulation is actually the same price at WM. I would keep doing what your'e doing.
You can always switch back and see if consumption increases a bit without a HM oil and go from there.
in all my very high mileage engines (over 200,000 miles) i use high mileage pennzoil in the summer only and regular yellow bottle or mobil 5000 in the winter. I prefer pyb in the winter but i don't buy it when the price goes way up
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No. you are wrong and spreading bad advice.
Originally Posted By: CrawfishTails
Stick with HM oil once you start. Seals swell a little more using HM oil, and you want to keep them that way.
Originally Posted By: CrawfishTails
Stick with HM oil once you start. Seals swell a little more using HM oil, and you want to keep them that way.
Why not just continue to use HM oil? I have seen several members here on the site state that they used HM oil in their new vehicles starting with its 1st oil change.
Unless you are wanting to switch back to a dino oil for cost reasons.
Unless you are wanting to switch back to a dino oil for cost reasons.
Originally Posted By: BlueOvalFitter
Why not just continue to use HM oil? I have seen several members here on the site state that they used HM oil in their new vehicles starting with its 1st oil change.
Unless you are wanting to switch back to a dino oil for cost reasons.
If HM oil does its job in an older, brittle-seals engine, then the seal swelling conditioners will actually swell the seals slightly. Why take the chance by switching back to a regular non-HM oil after usiing HM oil? Why not simply stay with an HM oil? They are easy to find, priced about the same, available in synthetic.
Originally Posted By: Oil Changer
No. you are wrong and spreading bad advice.
Originally Posted By: CrawfishTails
Stick with HM oil once you start. Seals swell a little more using HM oil, and you want to keep them that way.
See above. Seals can swell with swell-conditioners, its a fact. If the seals were already performing well (not aging), then the seals MIGHT not swell so far where its a problem. The point is, Why Take The Chance? Common sense wins.
Why not just continue to use HM oil? I have seen several members here on the site state that they used HM oil in their new vehicles starting with its 1st oil change.
Unless you are wanting to switch back to a dino oil for cost reasons.
If HM oil does its job in an older, brittle-seals engine, then the seal swelling conditioners will actually swell the seals slightly. Why take the chance by switching back to a regular non-HM oil after usiing HM oil? Why not simply stay with an HM oil? They are easy to find, priced about the same, available in synthetic.
Originally Posted By: Oil Changer
No. you are wrong and spreading bad advice.
Originally Posted By: CrawfishTails
Stick with HM oil once you start. Seals swell a little more using HM oil, and you want to keep them that way.
See above. Seals can swell with swell-conditioners, its a fact. If the seals were already performing well (not aging), then the seals MIGHT not swell so far where its a problem. The point is, Why Take The Chance? Common sense wins.
Originally Posted By: Oil Changer
No. you are wrong and spreading bad advice.
Originally Posted By: CrawfishTails
Stick with HM oil once you start. Seals swell a little more using HM oil, and you want to keep them that way.
I agree with CrawlfishTails and in that case you are wrong in the rebuttal.
The vehicle is 18 years and in good condition.
It has been on a diet of HM oils for the last 10 years and the oil chemistry is well established within the engines internals and the engine seems to like the HM oils here.
There is no benefit to switch at this late stage other than for experimental reasons, give BITOG something to talk about or boredom which is pretty dumb thing to do at this point in time IMO given the OPs success to date.
I am glad the OP posted as he has brought some real world experience here and he has found the magic elixir for his engine in this instance which most BITOGers are still searching for.
There is no compelling reason or evidence to change anything here.
No. you are wrong and spreading bad advice.
Originally Posted By: CrawfishTails
Stick with HM oil once you start. Seals swell a little more using HM oil, and you want to keep them that way.
I agree with CrawlfishTails and in that case you are wrong in the rebuttal.
The vehicle is 18 years and in good condition.
It has been on a diet of HM oils for the last 10 years and the oil chemistry is well established within the engines internals and the engine seems to like the HM oils here.
There is no benefit to switch at this late stage other than for experimental reasons, give BITOG something to talk about or boredom which is pretty dumb thing to do at this point in time IMO given the OPs success to date.
I am glad the OP posted as he has brought some real world experience here and he has found the magic elixir for his engine in this instance which most BITOGers are still searching for.
There is no compelling reason or evidence to change anything here.
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