Motul 4100 Power 15W50

[w126]

Just got this for my 1991 Mercedes 420 SEL
Live in midwest and I drive only in summer with occasional short drives in winter when sunny...

This oil is much thicker than the older Diesel Shell Rotella T4 (15w40) that I used.
Is this a problem? it has good zinc and phosphorous for my flat tappet...
API SL and Mercedes 229.1 approved.

Would it cause more wear than the T4?
should I switch back to 15w40 in maybe T5 Rotella....

 

[kschachn]

Approval is what matters. If the winter rating is appropriate for your expected starting temperatures then no problems.

Why would you think it might cause more wear? Film thickness prevents wear, not causes it.

 

[w126]

Approval is what matters. If the winter rating is appropriate for your expected starting temperatures then no problems.

Why would you think it might cause more wear? Film thickness prevents wear, not causes it.

Just concern about starting it up in my garage in the winter when it is like close to freezing 32F
Many people with same cars do 20W50 in summer as well.
15W40 would flow better at startup, no?

 

[ARCOgraphite]

Seems like overkill, maybe @OVERKILL can respond. Low power V8 Gasoline engine?

 

[kschachn]

Just concern about starting it up in my garage in the winter when it is like close to freezing 32F
Many people with same cars do 20W50 in summer as well.
15W40 would flow better at startup, no?

They both have the same winter rating. Both will be pumpable at freezing. Flow is not a consideration as long as it can be pumped.

 

[userfriendly]

If you're woried about cold starts, Mobil 5w50 Super car Dexos R would be an option.

 

[w126]

They both have the same winter rating. Both will be pumpable at freezing. Flow is not a consideration as long as it can be pumped.

I like it because it is not fully synthetic. I do not want full synthetic and I do not want to argue why. Looks like good quality oil, and it is recommended by Motul site. SL API (zinc 1100, Phosphorus 1050, Calcium 3080, Moly 100). It is good for a flat tappet like my engine... just little thick..... Again I am comparing it to Rotella T4 which is really thin...

 

[kschachn]

I like it because it is not fully synthetic. I do not want full synthetic and I do not want to argue why. Looks like good quality oil, and it is recommended by Motul site. SL API (zinc 1100, Phosphorus 1050, Calcium 3080, Moly 100). It is good for a flat tappet like my engine... just little thick..... Again I am comparing it to Rotella T4 which is really thin...

I had no idea you did or did not wish to argue about base stock. The winter rating is agnostic to this and indicates the cold-weather performance regardless of the composition.

The Rotella is not "really thin", I'm not sure where you get that notion. It is a 40-grade oil. Look at the PDS for viscosity if that's really a consideration, but the HT/HS is a better indicator. The Rotella product has more than sufficient HT/HS here.

But beyond ancillary objections, back to your original question. The Motul product will not cause more wear and is not a problem.

 

[OVERKILL]

I like it because it is not fully synthetic. I do not want full synthetic and I do not want to argue why. Looks like good quality oil, and it is recommended by Motul site. SL API (zinc 1100, Phosphorus 1050, Calcium 3080, Moly 100). It is good for a flat tappet like my engine... just little thick..... Again I am comparing it to Rotella T4 which is really thin...

Both are likely using hydrocracked bases. Most Group II is produced the same way as Group III, the cracking treatment is just less severe.

@kschachn has given you good answers here.

One question: What is the grade or specification Mercedes calls for?

 

[w126]

Both are likely using hydrocracked bases. Most Group II is produced the same way as Group III, the cracking treatment is just less severe.

@kschachn has given you good answers here.

One question: What is the grade or specification Mercedes calls for?

MB 229.1

 

[OVERKILL]

MB 229.1

I think you'll be fine, likely a bit unnecessarily thick but it's probably cost effective compared to other products with that approval like Mobil 1 FS X2 5W-50.

 

[twX]

A 15W50 will be fine for starting an engine at 32 F. That said, it is on the thicker side, even for a 15W50 (19.8 cST at 100 C), and has a low viscosity index (148), so it's not the best oil for cold weather, but any difference in wear vs a thinner oil will be minimal to non-existant. Fuel economy will be a bit worse.

The thing about 50 weight oils is that they don't necessarily protect better than 15W40 weight oils at high temperature. The minimum HTHS specification for both weights is 3.7. I have seen 50 weights with HTHS of only 3.74, and 40 weights with an HTHS as high as 4.7.

For 0 to 10W40 the minimum HTHS 3.5, the same as the euro 30 weight that is probably recommended by Mercedes, so even a 15W40 will provide additional high temperature protection, and you can look for a 40 weight oil with a higher published HTHS if you really think your oil temperatures get high enough to warrant it. Unfortunately, Shell and Motul don't publish this info.

All that said, run the 15W50 for now and don't worry about it.

 

[w126]

A 15W50 will be fine for starting an engine at 32 F. That said, it is on the thicker side, even for a 15W50 (19.8 cST at 100 C), and has a low viscosity index (148), so it's not the best oil for cold weather, but any difference in wear vs a thinner oil will be minimal to non-existant. Fuel economy will be a bit worse.

The thing about 50 weight oils is that they don't necessarily protect better than 15W40 weight oils at high temperature. The minimum HTHS specification for both weights is 3.7. I have seen 50 weights with HTHS of only 3.74, and 40 weights with an HTHS as high as 4.7.

For 0 to 10W40 the minimum HTHS 3.5, the same as the euro 30 weight that is probably recommended by Mercedes, so even a 15W40 will provide additional high temperature protection, and you can look for a 40 weight oil with a higher published HTHS if you really think your oil temperatures get high enough to warrant it. Unfortunately, Shell and Motul don't publish this info.

All that said, run the 15W50 for now and don't worry about it.

Thanks for the insight.
How does the Motul compare to the Shell T4 or T5 (Notice I did not mention T6 because it is Synthetic).

 

[kschachn]

Compare in what way?

 

[ChrisMU]

I have used 15w50 (Mystik JT-8… blend) in my (sold) ‘85 GMC van 305 V8, ‘76 Gremlin 232-I6, and some OPE. No issues at all with the GMC or OPE. The Gremmie does make a bit of valvetrain noise (this was in 50 degree F weather), but that car is a recent acquisition, and I can’t rule out the oil filter or other factors being an issue. According to AMC enthusiast groups, those engines can be persnickety about oil filter selection.

For anyone interested, 5 gallon buckets of JT-8 are on sale for $69.99 at Blain’s Farm & Fleet after $20 rebate. It has good zinc levels.

 

[w126]

Compare in what way?

quality....

 

[kschachn]

quality....

I’d use the Motul product but “quality” is pretty vague. The Motul has a better base stock composition.

 

[twX]

Thanks for the insight.
How does the Motul compare to the Shell T4 or T5 (Notice I did not mention T6 because it is Synthetic).

I believe the Motul 4100 is a synthetic. All of these oils have a healthy amount of ZDDP and detergents and a good TBN. The T5 and T6 aren't as shear-stable as the T4, and so they tend to thin out over time in some engines. For this reason I would probably stick with the 15W40 in your climate. This grade has a higher minimum spec for HTHS as well.

The Rotella line doesn't have the MB 229.1 approval, but I doubt that meeting that old standard is important. Here is the comparison of the MB 229.1 spec with a few of the more modern standards that the Rotella T4 15W40 meets. The Rotella line certainly has a more impressive list of approvals than the Motul.

 

[kschachn]

The Rotella line doesn't have the MB 229.1 approval, but I doubt that meeting that old standard is important. Here is the comparison of the MB 229.1 spec with a few of the more modern standards that the Rotella T4 15W40 meets. The Rotella line certainly has a more impressive list of approvals than the Motul.

The Rotella product has one approval. But on the other hand the Motul 4100 doesn't actually have Mercedes-Benz 229.1 approval, is it even current? No matter really, it isn't much of a requirement.

 

[w126]

I’d use the Motul product but “quality” is pretty vague. The Motul has a better base stock composition.

Hi:

Base stock meaning that the mineral oils (I am guessing around 80% of semi synthetic products) would be of better quality?
What do you think of the Calcium 3000 and Molly 100 compared to the others..