2001 LX - Mobil 1 ATF and oil? (1 Viewer)

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Seems weird to do a bracket instead of just ranking them. Just tell me which one to buy! 🤣
Amsoil and Pennzoil Ultra Premium are nearly identical, but the edge went to Amsoil for twice the price. I can usually get the Pennzoil from Walmart or Amazon for under $30 a jug.

I must be getting old - I remember when oil was under $2/qt. :(
 
Amsoil and Pennzoil Ultra Premium are nearly identical, but the edge went to Amsoil for twice the price. I can usually get the Pennzoil from Walmart or Amazon for under $30 a jug.

I must be getting old - I remember when oil was under $2/qt. :(
YES! $1ish. but I am sure others can remember under a buck
 
Ah, Project Farm. Great channel. I thought I remembered a video on HM vs. regular oils, which he did (M1 and ST). I re-watched the video this AM to beat a dead horse. He tested the potential for seal swelling by soaking O-rings and pieces of rubber and found basically no difference between M1 HM and M1 regular (which is consistent with my experience - whatever additive they use for seals doesn't do much as the M1 HM really didn't stop any oil leaks for me). He also found the HM has better wear protection than normal M1 and overall performed better than normal M1 in the other tests. This is also consistent with Mobil stating the HM has a higher viscosity base stock than normal M1.
 
I like PF YouTube channel. I watch his stuff often. He's made a nice business out testing products.

But this video did not prove anything, with respect to HM oil long-term affect on rubber. Except some swelling. perhaps!

Have you called Mobil or Mobil 1?
Perhaps they reformulated, since I called. When I was told by Mobil 1 how addictive HM oil is! Learning that, was all I needed to know. I'll not use!

Let take a peak at PF YouTube video testing of HM oils. Which was not real world use:
1) Mobil 1 stated: "if used for two oil changes". Which is 15,000 miles / two years. Or 40,000 / 2 years if EP used. That is an average of 150 hours or w/EP 400hrs of hot run time, at average of 50MPH. Also worth noting; Real world is with many heating and cooling cycles (expansion & contraction with greater changes temps). Very different than just on a burner in a tea pot, for a few hours.
2) What happens to rubber. After long-term use, if HM is no longer used. Not just a few hours than wiped off.
3) The instruments he used for measurements, were not of lab grade. For instances; He used a caliper to measure thickness of O-ring. Which he did show thickened, in O-ring with HM oil. But even my Mitutoyo digital OD micrometers or even the newer High-Accuracy Digimatic® Digital Micrometer – with 0.1µm resolution measurement. Are not recommended for rubber O-rings. The size of contact surface and fiction of clutch, are different in rubber O-ring micrometer. Scale is what, a postal scale.

His test did show some increase in size of O-ring. What would be even more interesting. If he heated for few hours daily, taking temp up than down twice a day for 5 day in a row, letting cool to 68f and down to -10F other times. Doing so after years of convention oil use. Then after two years of HM oil heating cycles. Change from HM, to non HM.

Do think results may be different :hmm:

Would be great if every vehicle came with logs books, like and aircraft engine. I for sure would avoid any that used HM oil.
 
To provide further clarification and evaluate if I may be harming the seals in my GX using M1 HM (I really don't want to have to replace the cam seals in the future as it's a PITA), I reached out to Mobil 1 technical support last night. They were very responsive and helpful. Please see the email exchange below.
Mobil_Correspondence.jpg

In summary:

1. Mobil 1 has a seal conditioner. They don't share what the seal conditioner is unless it's business critical or you sign a NDA. They didn't confirm or deny that it is or isn't a seal sweller, although I asked that question specifically. .
2. They recommend it for high mileage engines that are leaking.
3. They confirmed, in writing, that anyone can switch back to regular oil at any time, and that it's a myth to require HM oil to be used for the life of the vehicle.

I cannot speak for other HM oils or older version of M1 HM. I've only used M1 HM and Valvoline max-life HM semi-synthetic and have had great success with both of them in multiple Japanese and domestic vehicles, including instances where I swtiched back and forth with non HM and had no leaks appear.

So far, no positive, detailed evidence that M1 HM causes seal swelling has been provided by anyone on this forum or other sources I have found. Conversely, there is a wealth of evidence including my experiences using M1 HM for nearly a decade in 4 vehicles (domestic + Japanese, up to 24 years in age with well over 200K), the Project Farm testing, and information from Mobil that provides no indication that M1 HM swells or harms seals are all.

If someone does have positive, verifiable evidence (i.e., not anecdotal) of M1 HM (specifically) causing seal swelling, I would like to see it. If it can be proven that it swells seals, I'll stop using it in my GX and switch to M1 regular 5w40 oil, as I really want to keep those cam seals fresh as long as possible.
 
Reading your email transcript, I see they've changed their statement on HM oil.

So I called, asking why and when the change. Speaking with 3 different reps, all obviously English was not first language. None could answer, nor tell more about additive packages. Last rep said ,they are a contact support center, not employees of Mobil 1.

So either they changed the additive. Which you'd think they be proud of and publish somewhere, which I yet to find!
Or
Legal re-wrote their manuals.

I've seen no reason to used HM oil, even at 400K miles. The million mile 4.7L Toyota, had no mention of it use to my recollection. Even if I do see the need. Until I've clear info, I'm stay clear of all HM oil

In search Mobil, I found a release of triple action in 2022. Which page had a dead link to High Mileage Oil info.

Only thing I found was: Mobil 1 High Mileage 5W-30 Motor Oil is not dexos approved. Using a non-dexos approved oil may void your warranty.
 
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Frankly I think not using it is fine - per my earlier posts AT-205 does a better job of conditioning seals. I've mainly used M1 HM out of habit. Project Farm's test data does indicate it might perform a bit better, but normal M1 is good to start with. I can't conclusively prove any tangible real-world benefits to M1 HM oil, although I think it's been established that it's not hurting anything either.

I'll likely keep using it as I have 3.5 jugs of it in my shop. Perhaps the higher viscosity base stock might provide some benefits for my 2UZ which sees a lot of towing miles with high rpms climbing hills.
 
The rule of thumb I've been told was not to use HM unless the vehicle had leaks, as the HM additives were meant to swell things to help stop leaks and unnecessary for vehicles that were already sound in that regard and could even harm seals by swelling them unnecessarily. Not sure if this is true or not.
 

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