Originally Posted By: Brigadier
So, is CATERHAM and engine or oil engineer? Is AEHaas? What makes their OPINIONS gospel?
Haven't seen too many pearls of wisdom coming off your keyboard, bucko, so I think the green-eyed monster is talking. Their "opinions" are based on a lot of study and they usually back their "opinions" up with information and references. They also respond well to challenges of their "opinions" so if you don't agree, by all means challenge them on the facts with some of your own.... but you better bring a lunch. That's not to say I always agree with them either but I admire and appreciate the mental effort they put into formulating their "opinions." One liners like yours just don't carry much weight.
Originally Posted By: Shannow
Originally Posted By: Jim Allen
Ranchu: I presume you were not being intentionally insulting but it came across that way to me and my annoyance with this whole "one size fits all" argument escaped the boundaries of my good manners. I'm not "sorry" exactly but wish I had written my first sentence differently.
And I presume that you are not intentionally being arrogant and aloof with your circular defence of thin oils in this and other threads.
I've explained previously how bearing design and lubrication are carried out...and Ford are changing their designs to suit the thinner oils, changes which actually increase the drag of the bearings to increase "protection" (lower projected pressures, and smaller radial clearances), but we get back to "if they specify it it must work, and because it works, they specify it, and who are you to have another opinion"...in spite of engineering fundamentals.
Circular defense of thin oils?
My "opinion" has evolved several times over the time I've been on BITOG, as many people's have, but I don't know how you can read my posts in this thread and say that. The gist of what I said above is basically, "As thick as necessary, as thin as possible." Or "As thin as possible, as thick as necessary." Whichever makes you feel better. I said above to Ranchu;
"The problem is you, and many others, want to apply some "one size fits all" filter to an oil viscosity question. It isn't that simple. The range of "what works" is vast, evidenced by the wide range of oil viscosity in use around the world. What is optimal is a question specific to climate, engine design, operational situation and many other factors. I don't know why people have to continue to argue this thick vs thin thing."
and;
"I think viewing this in terms of a "Perspective" is a mistake. Science should dictate the oil choice. Nothing more. I suppose we can argue about the science, but then we must get into deep specifics... the exact engine and the circumstances in what that particular engine is operated. Overall, the presumption must be that, for the most part, the OEM's recommendations are valid, if not optimal, for their product. They have applied the science in detail. We often don't even have the required information to second guess them scientifically."
How exactly am I defending thin oils?
Shannow you claim to have an engineering background. Do you also have the resources to run the same sorts of qualification tests a big company like Ford uses to certify oil? Until you do, I submit that, if you are intellectually honest, you have to give those tests a great deal of credence. If your mind cannot stretch to that degree, in light of the resource differences between your theories and opinions and their testing, who is the arrogant one?
I have seen bits and pieces of information from the days in the '90s when Ford was qualifying 5W20 oil. It must have cost millions. Wish I knew more but I do have a pretty large file on the qualification testing done for one small part, a small inline filter that cost Ford about $10 and was used only on reman transmissions. That file is an eighth-inch thick. I'll guess Ford spent $30K to qualify that one small part. This give me some perspective on whether to trust them (not implicitly but sufficiently) on other things.
Given how long Ford has been using light oils and how many millions of engines are running on it, and that we haven't seen a rash of prematurely dead Ford engines, those qualifications simply have to be given a lot of weight on a day to day practical level as well. We all know governments and companies get things wrong on a massive scale sometimes, but I don't think the data and record supports an opinion that Ford's change to 5W20 falls into that category.
When did Ford start adopting 5W20. Late '90s, early 2000s? Only now they are changing bearing designs to suit? How strange.
