Mobil 1

[gnj588d]

Hi and Happy new Year to everyone .Just going to do an oil change using mobil 1 15w50 fully synthetic,
but have been advised that it has been superseded by Mobil 1 10w60 have noticed some of the group are using the 15w50.
any help on the suitability of the 10w60 would be appreciated.cheers.Mike.   

[mdsalemi]

Mike, I think it depends on your country. On the USA Mobil 1 website, 10W-60 does not appear on their summary lists, the latest dated April 2013. When I searched for the oil by that viscosity, I came up with a spec sheet--from Mobil (Turkey).  

Just follow their guidelines and look what is available to you. Here, the 15W-50 has the highest levels of zinc & phosphorus in their product offerings (excepting their specialty racing oils not recommended for street engines) which is what we are looking for. Every year or so, new formulations are offered and 10W-60 may be, eventually, the replacement for 15W-50. As of today, it does not look like its offered yet.

In the USA, Mobil 1 has a tech support line; they speak English; and are pretty knowledgable about current offerings. Perhaps the same in UK?

[gnj588d]

Hi all.
Just spoke to Mobil technical dept the say Mobil 1 15 w 50 has been replaced with Mobil 1 10w60 both have high zinc content do you think this is suitable for my 66 230
my engine is running at full oil pressure and uses no oil, been advised it might be to heavy by a well respected member.Many thanks Mike.

[jameshoward]

It may be. But I do think that some folk still bang on about what's right for the car solely because the original owners manual says ATF here, or 10w50 there, etc. Some may think that 10w60 is too heavy because the car when very cold may benefit from something with better viscosity. I'd humbly suggest, however, that we don't use these cars in the conditions they were originally designed to operate in. So, few if any of us would leave a car out in the penetrating cold during winter and use an oil with a fluidity similar to cold marmite. Most cars are kept inside, and so the viscosity issue is perhaps less relevant than it was 50 years ago. Plus, oils have moved on so significantly during this period.

If you've been using Mobil 1 for a while, and the advice from Mobil is that 10w60 is the replacement for the 15w50, I wouldn't have a problem with it.

Personally, I use Halfords classic oil (made by Comma I understand) as I change it yearly/3k miles. It has a high level of zinc, so they say. My car runs perfectly well on it. My flirtation with Mobile 1 lasted one oil change...leaks ensued and I changed back quickly. After a few years and a tube of seal conditioner, the leaks have gone.

I'd suggest that you consider how you use your car and what conditions you start it in (how cold) and go from there.

[mdsalemi]

Correct me if I'm wrong:

Isn't the cold viscosity the lower number with the W suffix? Thus, 10W-60 is more fluid at cold temps than 15W-50? And the higher number is the high-temperature viscosity?

[Jonny B]

Yes, the lower number represents fluidity/visco for the colder conditions.

Here is one reference I found on the net (it must be right…..?!)

Viscosity ratings: Oil is rated and identified by its viscosity, which determines its ability to flow.

Two types of oil are on the market: single-viscosity oil and multi-viscosity oil. Almost every vehicle is designed to run on multi-viscosity oil. The lower the number, the thinner the oil and the more easily it flows. In 10W-40 oil, for example, the two numbers mean that it’s a multi-viscosity oil. The 10W is an index that refers to how the oil flows at low temperatures (in Winter); 40 refers to how it flows at high temperatures.

Here is another
http://www.upmpg.com/tech_articles/motoroil_viscosity/

[jameshoward]

Correct me if I'm wrong:

Isn't the cold viscosity the lower number with the W suffix? Thus, 10W-60 is more fluid at cold temps than 15W-50? And the higher number is the high-temperature viscosity?

Michael,

My first point is this: I'd thoroughly recommend that members take your advice over anything I can offer. I'm sure you're quite correct.

My other more general, less educated point remains, however. I do think that in relation to oils and wotnot we worry too much about viscosity and grades and forget that the use of our cars has changed over time. We should worry less about what a 50 year old manual says and take the advice of contemporary specialists.

Maybe.

Or not.

It's been a long day. My apologies for any confusion caused by my incorrect (and therefore very limited) understanding of lubes...

 

[mdsalemi]

James, that link that JonnyB provided (from Amsoil) was written in a clear and easy to understand style--just about oils, not our specific cars.

Now when you are real tired, delve deep into the the subject of "Pour Point Depressant Additives" for a real laugh...

[clembeauch63712]

Hi all; Happy New Year to all, I will add my 2 cents worth. I a formily taught mechanic of the 60's for what that's worth? Use Shell 15-40 diesel purchased at the big box store walmart.. It is zinc & phos. fortified , meets all the Detroit & Cummings ratings. After all our engines are more like high revving truck engines. I did 1150 miles to /from CT. & Williamsburg in relative warm weather and didn't baby the car 517 miles in 8hrs flat to home. I used 1/2 Quart of oil. that was ave speed of 62 mph including 10 mile traffic jam & quick pit stop for fuel. I ave. 26 miles per gallon on the trip. Im a believer that thicker is not necarilly better..  I use 75-90 Lucas gear oil in the Diff. & Honda manual trans lube in the gear box (Honda MTL) it is like a 10-30 oil. My car has 88,000 original miles a nothings rebuilt.. Cheers; Clem

[garymand]

Thanks Mike, good articles in Amsoil.  good to know the new group III rating is no longer real synthetic.  

I couldn't find a clue how to determine group III or IV on the bottle labels.  Apparently the Mobil 15W-50 / 10W-60  is synthetic and should give the best protection?  Both for long oil changes and wear protection?  

I have also leaned toward the diesel oils but wonder if they protect at high RPMs.  I vagly remember a warning about using diesel (motor) oils in a w113.  Anyone have data?

[Louiehenry]

I use 15w40 in my pagoda and at high rpms it protects just as well as others. Ironically enough, my diesel pick up uses 10w30!!

[gnj588d]

Thanks for all your replies oil change due in a couple of months so will decide then.
                                                                                        Cheers .Mike.

[franjo_66]

Mike, I have been using the Mobil 1 15W-50 for over two years now. My engine has never been rebuilt and has a documented 66,000miles

All I can say is that I have no issues with leaks at all. I change the oil & filter religiously every 6 months irrespective of mileage. Oil looks in great shape with no sludge, etc.

So I can highly recommend Mobil 1 based on my experience

[bsimaz]

I believe that it depends on how and what you have using in the past. 
If you have been using regular oil and have not had any work done on the engine, a
synthetic oil will cause leaks. I happened to me when I tried to change.  The years of
small amounts of gunk and sludge build up keeps the small leaks from happening.  When
a synthetic is introduced with the modern additives and cleaners my engine started leaking
and I had to switch back.   All the leaks stopped. 

If, however, you have just rebuilt your engine and run only synthetic in it, you will  be alright.

I was always told to run 20w50.  The tolerances of these engines built in the mid/late '60s needed the
thicker oil to lubricate correctly.