Mobil1 High Mileage frustration...

wemay

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My Brother recently sold his 2007 Nissan 350Z (382K miles) and bought a newer one, 2018 with 25K miles. He has about 4 jugs of Mobil1 HM 5W-30 in the garage he wanted to use. So i showed him the video where Mobil1 uses a Camry to show this oil did a great job protecting the Toyota for 500K miles (used in the Toyota since new). So he called Mobil1 just to be safe....twice. And got the same answer...."not recommended due to seal swell agents in the oil". So i called and asked about the video??? I got a few "ahhhh, um, let me check....". Both times they came saying the video is not representative of a new vehicle and they don't recommend it. WHAT!?

My brother promptly took the oil back to Walmart and they graciously exchanged it for PP. He didn't even want to deal with Mobil1 anymore after that. He also called Mobil1 back to tell them not to honor the rebates he sent in since he returned the oil.
 
If that's their actual advice it makes me wonder how ExxonMobil snuck their HM oils past the API.
I think the API uses the ASTM D7216 test for seal compatibility testing. I wonder if @MolaKule happens to have a copy of this document and can share some details on what the test entails:

 
I think Valvoline is the only major oil blender that openly recommends using their Maxlife oil in all engines. Pennzoil and Mobil 1 will recommend against using their High Mileage oils on new engines.

If it was M1EPHM I believe they absolutely would have told him to use it. One of the interesting mysteries of M1HM is that it cannot meet the Resource Conserving "Starburst" for some reason but the EP version does...
 
The only high mileage oil I care to use is Valvoline Maxlife, preferably the synthetic version. I am not convinced that any other HM oil is worth a darn in comparison.

I can say that M1HM is very good at reducing leaks. Their AN esters are second to none. But MaxLife is great...
 
...And got the same answer...."not recommended due to seal swell agents in the oil"....

ALL engine oils have Seal Well agents in them.

Here is one seal test posted by Solarent some time ago.


and some older QOTD threads:


 
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Both times they came saying the video is not representative of a new vehicle and they don't recommend it. WHAT!?
The problem is seal swell.

The Gold Standard for seal swell is ordinary solvent-refined motor oil as used in the "good old days" of cork and rubber elastomers.

For example, when Mobil developed the largely PAO-based Mobil 1 back in the '70s, it added a bit of ester to it to avoid the seal shrink which PAO alone would have caused.

All the major additive manufacturers make seal swell additives

Afton Chemical Seal Swell Additives

for adjusting seal swell in finished products.

The "High Mileage" oils cause elastomers to swell more than the Gold Standard to compensate for shrinkage and age.

What would have happened is that after using High Mileage oil in a newer engine for an oil change or two, when the engine was switched back to non-High Mileage oil it would tend to leak.

You don't want to swell the seals until they're aged and beginning to leak.
 
Both times they came saying the video is not representative of a new vehicle and they don't recommend it. WHAT!?

This appears to be miscommunication.

If the video is this one:

Mobil 1 High Mileage

"high mileage" refers to the 500,000 miles, not Mobil 1 High Mileage oil.

Notice the picture of containers of the High Mileage formula come AFTER 02:16 and "75,000" miles, which agrees with their advertising that those oils are for "those with more than 75,000 miles".

The video itself never tells which formula or viscosity was used in the test.
 
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