Are today's full syn HM oils thicker than non-HM?

[cheesepuffs]

I remember a few years ago before Maxlife blend became resource conserving, people liked that it was on the thick side for its grade. It was commonly known that high mileage oils ran a bit thick. Now with Platinum High Mileage, Maxlife Syn High Mileage, etc, are these modern synthetic High Mileage oils still thicker than their regular synthetic counterparts? Or is that a thing of the past.

 

[mx5miata]

I never heard of high mileage oil being thicker just additives like seal conditioner. if the oil is 5w30 its a 5w30 high mileage or non. of what I know anyway.

 

[ka9mnx]

Some are, yes. I'm only familiar with Mobil 1 products.

Mobil 1 5w30 has an HTHS of 3.1 and Mobil 1 High Mileage 5w30 is 3.1 so they are basically the same

Mobil 1 10w30 has an HTHS of 3.0 and Mobil 1 High Mileage 10w30 is 3.5 so the HM is thicker.

I could be wrong but I believe HTHS is what defines a "thicker/thinner" oil. With than thinking Mobil 1 10w30 is thinner than 5w30 at operating temps.

So it's not an easy blanket answer. You have to check the spec's.

On the other hand, The 5w30 V@100c is 11.0 and the HM is 12.1 which would make the HM thicker at op temps.

Someone help me out here!

 

[Whipcitywrencher]

Two that I know of with a higher viscosity are Mobil 1 syn. hm 5w30 and 10w30,
there higher than there reg.syn. counter parts.
Here's a list of oil's I've used or have in my stash.

A. Mobil 1 5w30 fullsyn. 100(11.) 40(61.7) vi index (172)
B. Mobil 1 10w30 fulsyn. 100(10.1) 40(63.2) vi index (146)
C. Pennzoil 5w30 platinum syn. 100(10.3) 40(56.9) vi index (170)
D. Pennzoil 10w30 platinum syn. 100(10.3) 40(63.3) vi index (150)
E. Valvoline 10w30 fullsyn. maxlife hm. 100(10.8) 40(67.2) vi index (151)
F. Valvoline 5w30 fullsyn. maxlife hm. 10(10.1) 40(59.0) vi index (160)
G. Valvoline 5w30 full synpower 100(10.2) 40(60.1) vi index (158)
H. Valvoline 10w30 full synpower 100(10.8) 40(66.8) vi index (151)
I. Pennzoil 5w30 platinum syn. hm. 100(10.1) 40(55.6) vi index (170)
J. Pennzoil 10w30 platinum syn. hm. 100(10.6) 40(65.1) vi index (152)
K.Pennzoil 0w40 platinum syn. euro 100(13.0) 40(72.2) vi index (183)
L. Castrol gtx magnatec 5w30 100(11.2) 40(68.6) vi index (156)
M. Castrol gtx magnatec 10w30 100(11.6) 40(71.51) vi index (157)
N. Mobil 1 High Mileage fullsyn. 5w30 100(12.1) 40(72) vi index (165)
O. Mobil 1 High Mileage fullsyn. 10w30 100(12.1) 40(78) vi index (149)
P. Quaker state Ultimate Dur. syn. 5w30 100(10.8) 40(60) vi index (178)
Q. Quaker state Ulitimate Dur. syn. 10w30 100(10.3) 40(61) vi index (157)
R. Quaker State High Mileage. synblend 5w30 100(10.7) 40(63.3) vi index (159)
S. Quaker State High Mileage. synblend 10w30 100(10.5) 40(68.4) vi index (141)
T. Pennzoil ultra Platinum syn 5w30 100(10.3 40(56.3) vi index (173)
U. Pennzoil ultra Platinum syn 10w30 100(10.4) 40(62.8) vi index (155)

 

[Indydriver]

Mobil 1 says:

“(HM has a) higher base oil viscosity to help reduce leaks and provide better high temperature protection”

For 5w30, XOM publishes these viscosity specs:

At 40C: HM=72 / STD = 61.7
At 100C: HM=12.1 / STD = 11.0

So, one must conclude that yes, at least at Mobil 1, HMs have higher viscosity or are “thicker” as you say.

 

[KCJeep]

A few still are. Last I was aware of, Castrol High Mileage, Mobil 1 High Mileage and Pennzoil High Mileage were all on the thick side of grade and thicker than their regular line up counterparts.

 

[mx5miata]

Wow API allows this

So I buy 5w30 High mileage and I'm not pouring 5w30, what weight is it?

Since I can't scientifically answer this my guess would be the additive pack in high mileage oils changes its properties at different temperatures and stress loads while maintaining its characteristics of the specified weight.

 

[cheesepuffs]

Originally Posted By: mx5miata
Wow API allows this

So I buy 5w30 High mileage and I'm not pouring 5w30, what weight is it?

Since I can't scientifically answer this my guess would be the additive pack in high mileage oils changes its properties at different temperatures and stress loads while maintaining its characteristics of the specified weight.


There is a tolerance for each grade. You can have two different 30 weight oils that are still slightly different but still fall within range to be called a 30 weight.

 

[PimTac]

Originally Posted By: mx5miata
Wow API allows this

So I buy 5w30 High mileage and I'm not pouring 5w30, what weight is it?

Since I can't scientifically answer this my guess would be the additive pack in high mileage oils changes its properties at different temperatures and stress loads while maintaining its characteristics of the specified weight.




Just in case you haven’t seen this;

https://www.bobistheoilguy.com/viscosity-charts/

 

[mx5miata]

thanks guys very interesting learn something new each day

 

[Garak]

Some are, these days, most are not. If they're ILSAC rated, they won't be appreciably thicker than their non-HM brothers.