It's just a specualation on my part, but I think they may just follow other companies. They were one of the first companies to mass market synthetic oil, but they lost a court case with regards to what is "synthetic oil", and now they do what others do -- using (a presumably) cheaper base stock, based on highly processed dino juice in addition to truly synthetic fluid(s).

How would that effect the performance, I do not know, especially since performance also depend on the additives (both amount and type) and to get API certified, there are some restriction on the amount of certain additives.

 

Exactly, Aurgathor. That's the crux of the entire argument, that M1 has changed course and followed other companies.

Once Mobil lost their case they had the opportunity to continue on the same path and use it for a selling point, or do what Castrol (and others) did and change the formulation.

While Mobil won't admit to their actions, they use lawyer words in the advertising and keep charging out the wazoo for what some folks feel is a lesser product.

Most people don't know the difference. Some people will never admit to themselves that Mother Mobil has changed something. And others simply move along to another product from another company.

I'm not saying M1 is a bad product. I'm only saying it may not be worth what they charge any more. And with that said, equal oil may be had for much less and better oil may be had for the same price.

Caveat Emptor - Let The Buyer Beware.

 

I couldn't have said it any better.

 

Anybody use the MotorCraft 5 -20W synthetic in the 7.3L turbo diesel? Is that advisable?

 

Yeah if you go to most of the syn oil pages, they do not state outright what is in their oil. They use wishywashy words like "high performance fluids", "sythetic fluids" etc. They usually don't say 100% PAO etc.

Since Mobil lost their suit years ago, "synthetic fluids" doesn't necessarily mean you are getting the real thing.

I have suspected that Valvoline and Havoline are just highly processed dino oils and that Mobil may be too. The mobil fluid appearance has changed a lot over the past 10 years. Sometimes dark sometimes light sometimes even maybe some particulates at the bottom of the can. I stick with these brands mostly out of past experience, and that is what a lot of companies rely on, we are creatures of habit.

As far as what Diesel oil is best, for the guy asking, I don't know. I have never owned a diesel and am no oil expert. I just read that many automotive syns are not appropriate for Newer Ford Diesels due to foaming. Read the spec and choose the oil accordingly. I think the top brands(Delo, Rotella, Chevron etc) would be excellent, but like I said I have no experience here.

Just my opinion,

Jim Henderson

 

I have experienced same out come. More power with synthetics. And one thing synthetics do is not break down. What breaks down due to heat is the additive package in oil, if anyone has a issue with that look at a air cooled engine or a race engine that has synthetic used in it, pan will be clean as a pin, dyno lube engine will have a black sludge in pan.

 

Talk about dead thread revival.