Why all the 'fuss' over M1 15W-50???

[addyguy]

Of all the M1 grades, the 15W-50 seems to have the most 'attention' paid to it - there are different 'types', that are distinguised by their 'cap color', red cap, silver cap...also, there is whether 'EP' 15W-50 is better than regular 15W-50...its all so bloody confusing!

What spurred this post is that recently Canadian Wal-Marts and Canadian tires started replacing M1 5W-50 with 15W-50. This 15W-50 is in a regular silver M1 bottle, with a matching silver cap, and an orange 15W-50 'viscosity' label. It says it meets SM requirements.

Which M1 15W-50 IS this - is it a 'new' Canadian-only, SM-spec 15W-50; or is it the vaunted 'silver cap' 15W-50, or is it 'red cap' 15W-50 in new packaging... reason I am asking is I have seen some great UOA's with M1 'mixes' using 15W-50 and a lower grade (Cutehumours run of 15W-50 and 0W-20 comes to mind), and I'm thinking of trying it for my Cavalier....

 

[FrankN4]

I "BELIEVE" this is the new Silver Cap 15W-50. It is SM rated but it is SM 50 grade so it has a ZDDP level of 1200 and a HTHS of 4.5. The 15W-50 EP also has the high ZDDP and high HTHS.

 

[addyguy]

Is this the one you use, Frank? I know C-H is using older 'EP' 15W-50 in his mix....

 

[FrankN4]

Yes, I use the M1 15W-50 Silver Cap. I have a some here and am trying to find a product code. One number is 98JK56, another is X27J7 5501, and the UPC is 71924 24813. I know of a few, 5 or 6, folk that mix 1 quart of M1 15W-50 with 3 1/2 quarts of M1 5W-30 TSUV and use it as a heavy 5W-30/light 10W-40.

One of the peculiarities of M1 5W-30 is that it has a thicker cSt on both the bottom end and top end. BITOG UOA,s reveal that the 5W will maintain its thickness over the 10W up to just over 5000 miles. Mixed with 1 quart of 15W-50, it will maintain a 30 grade cSt of 10 to just over 231F. It also gives you some decent moly, boron, calcium, and a ZDDP of around 900, and a HTHS of 3.4, or so.

Another popular mix is 2 quarts of M1 15W-50 and 3 quarts of M1 10W-30. This one gives much of the above benefits plus a HTHS of better than 3.6, almost 3.7.

I asked a Mobil 1 engineer, not a tech help person, if it was completely, absolutely safe to mix different grades of M1. He said, "yes, that is how we make them."

 

[aquariuscsm]

I used the silver cap 15W50 for a long time. Didn`t it basically replace the old red cap 15W50? I would never buy the extended performance unless it was on sale/clearance.

 

[slidetaker]

Does M1 15w50 stays in viscosity better than M1 5W50?

Given that there were UOAs here showing even M1 0W40 shears to a 30.

 

[HTSS_TR]

What is the HTHS of a mix of these M1 weights ? Around 3.5 ?

3 quarts 5W30
3 quarts 10W30
2 quarts 15W50
8 ounces VSOT

 

[FrankN4]

I don't know what VSOT is unless it is the Valvoline Oil Treatment, but just the oils, if they are the standard, not HM or not EP, the HTHS would be very close to 3.46.

 

[aquariuscsm]

Silver cap 15W50 is also said to be one of their few oils that`s group IV/V.

 

[aquariuscsm]

I`ve read here that engines running on M1 showed high iron levels on a uoa. What exactly is the cause of that iron level?

 

[Fordiesel69]

Originally Posted By: aquariuscsm
I`ve read here that engines running on M1 showed high iron levels on a uoa. What exactly is the cause of that iron level?


I experianced a x2 elevation in my iron using M1 5w-30. I would also like to know why. My PP interval cut this to an almost non existent wear. I have like 7PPM iron now. 12PPM is univerasal according to blackstone.

 

[OVERKILL]

But is it really wear?

 

[HTSS_TR]

Thanks Frank.
VSOT is Valvoline Synpower Oil Treatment. All M1 weight are standard, not EP nor HM. My estimated of HTHS for the mix was 3.4-3.6, because the very thick and heavy VSOT. This mix is good for summer but a little to thick for even mild winter in So Cal.

 

[FrankN4]

Originally Posted By: aquariuscsm
I`ve read here that engines running on M1 showed high iron levels on a uoa. What exactly is the cause of that iron level?


I do not know the cause, but if you research UOA's you will often, not always, see what I would call higher than average iron levels. However, I have my Toyota with 300,300+ miles and the last 260,000 are on Mobil 1 and it still runs great. My wife's 1999 Cavalier got Mobil 1 the day it came home from the dealer and it now has 206,500 miles and it is daily used, runs great. Of course I have other Mobil 1 success stories. I find it difficult to accept that this is wear metal or I should have no compression pressure or timing chains. The Toyota and the Cavalier both have every original engine part.

 

[BigJohn]

I ran some 15W50 in my motorcycle back a few months ago and it was amazing. Oil consumption went to near zero, the bike engine purred like a kitten and the shifting was silk smooth.

The only downside was a UOA (from another guy) showed that it sheared down a little too much in only 1500 miles. But honestly, my bike calls for 40wt as the standard and if this 50wt sheared down to a 42...then it would have been just fine.

What about the question about 15W50 being a group IV/V?