High Mileage Oils Oxidation Number

[Carlostrece]

I watched a Lake Speed video about High Mileage oils. He said HM oils show a higher starting oxidation number in VOAs, which he said is how we know they have extra seal conditioner in them.

Does it mean HM oils oxidize faster? Does it mean HM oils cannot last as many miles or as much time?

 

[Rand]

have you considered asking him these question.. in his youtube video comments?

Short answers:
No, No

 

[Carlostrece]

have you considered asking him these question.. in his youtube video comments?

Short answers:
No, No

I did post my questions in the comments section of his Youtube video about HM oils. I hope to get an answer from him. I am also curious to know the opinions of BITOG members.

 

[Tom NJ]

A higher starting oxidation number means that the oil has more of a component containing C=O molecular bonds. It may or may not mean extra seal conditioners. One would have to identify the source of the C=O bonds to determine its effect.

In any case, a starting oxidation number does not mean the oil oxidizes faster or does not last as long. If the source of the higher oxidation reading is an ester base oil it is likely more oxidatively stable that the main hydrocarbon base oil.

There are no official rules governing the ingredients or performance of High Mileage oils. Reputable formulators often do add some extra seal conditioners, but there are different chemistries available which may or may not affect the oxidation reading. Usually a significant boost in the oxidation number is indicative of an ester base oil component which will help condition seals.

 

[cheesepuffs2]

@Tom NJ would Euro or premium oils with a known higher ester content generally be as suitable for helping to condition older seals as a standard or lower-tier high mileage oil?

 

[Tom NJ]

@Tom NJ would Euro or premium oils with a known higher ester content generally be as suitable for helping to condition older seals as a standard or lower-tier high mileage oil?

Depends on the total formulation and type of ester. They all need to pass the seal compatibility specifications.

 

[cheesepuffs2]

Depends on the total formulation and type of ester. They all need to pass the seal compatibility specifications.

How tight is the window for seal compatibility? Basically, is the difference between regular an HM versions of the same oil possibly negligible because there's a certain ceiling anyway?

 

[Carlostrece]

A higher starting oxidation number means that the oil has more of a component containing C=O molecular bonds. It may or may not mean extra seal conditioners. One would have to identify the source of the C=O bonds to determine its effect.

In any case, a starting oxidation number does not mean the oil oxidizes faster or does not last as long. If the source of the higher oxidation reading is an ester base oil it is likely more oxidatively stable that the main hydrocarbon base oil.

There are no official rules governing the ingredients or performance of High Mileage oils. Reputable formulators often do add some extra seal conditioners, but there are different chemistries available which may or may not affect the oxidation reading. Usually a significant boost in the oxidation number is indicative of an ester base oil component which will help condition seals.

You mention ester. I think LSJ mentioned ester when he was talking about higher starting oxidation number.

 

[Tom NJ]

How tight is the window for seal compatibility? Basically, is the difference between regular an HM versions of the same oil possibly negligible because there's a certain ceiling anyway?

The specification ranges are pretty wide. There is room to change elastomer compatibility with additives, but must be balanced across the different elastomers, which may respond differently to different additives. Here are the specifications for SN, the latest I have handy:

 

[Tom NJ]

You mention ester. I think LSJ mentioned ester when he was talking about higher starting oxidation number.

Esters have the C=O bond and so will increase the oxidation number result, but do not reduce the oxidation stability of the oil - in fact they often increase the oxidative stability depending on the ester. Esters are also polar and increase swell and softening of elastomer seals.

For more information on esters see: Esters in Synthetic Lubricants

 

[Carlostrece]

I did post my questions in the comments section of his Youtube video about HM oils. I hope to get an answer from him. I am also curious to know the opinions of BITOG members.

Still no reply from Lake Speed Jr AFAIK. It's possible that he replied, but I didn't receive a notification. I'll go have a look later.

 

[Carlostrece]

Esters have the C=O bond and so will increase the oxidation number result, but do not reduce the oxidation stability of the oil - in fact they often increase the oxidative stability depending on the ester. Esters are also polar and increase swell and softening of elastomer seals.

For more information on esters see: Esters in Synthetic Lubricants

Thank you Tom. You're a wealth of info and very helpful. I appreciate you.