I ran royal purple 10W-40 synthetic in my TurboII K-car. When I put another one together (totaled by an ML320) I will run it in that one also.

 

personally i always used castrol 10w-40 in newer engines and 20w-50 on my older motors and change it religiously every 3000 miles

 

FWIW I worked in part as a Royal Purple distributor for a rather well thought of company, shoot Josh and Don might know them, Warehouse West in Renton, and even in that positition try as I might I couldn't get them to actually tell me what their oil actually was. Even when their sales rep came by, I got shirts and stickers but no answers. I was trying to find out if they used a refined dino class III base stock or a true synthetic PAO type IV base stock, or a mix. Because of that and other information that leads me to believe that it is type III I will not use or recomend it and say it's over priced snake oil.

Of course the Rotella T6 "Synthetic" I use is also a Type III oil, but a very good and reasonably priced one. Right now I only know of 3 brands that are true type IV based oils, Amsoil, Redline, and Mobil 1

EEEECK This Don is why I make my arguments.

 

It matters at start up when the engine is cold. When the engine is warm, then you are correct. Before the engine is warmed up, the ambient temperature outside is a factor in what oil you run, and at what viscosity.

You are confusing viscosity, with thickness and density. Viscosity is not thickness, (a very comon mistake) it's the rate of resistance to friction or flow. I think you will find that the viscosity of multiweight oil is higher when it's hot, than when it's cold by design, even though it's thinner when hot.

But you don't have to take my word for that either...

Understanding Absolute and Kinematic Viscosity


My favorite explanation of viscosity from the above page is the mayonnaise vs. honey viscosity example. Mayonnaise will not flow out of a jar like honey, but which one is thicker, mayo or honey?... Which can you stir easier, mayo or honey?..

The viscosity of multigrade oils increases with temperature, but it also gets "thinner" with heat. Think mayo vs honey again...

For people who know me, I do not argue. I will speak up if I think you are wrong or mistaken. Your advice may ruin peoples engines, and I will stand by that assessment. It's a date I picked for clarification, nothing more. In the mid 90's Ford started recommending oils in lower viscosities, 5w-30 recommendations are comon begining in '95 for example. There is a reason for this. Better measuring techniques of clearances using computers, and some of the first rollerbearing camshaft engines started rolling off the assymbly line in the '90s. My ex wife's 1997 taurus had such an engine etc... Putting 10w-40 in that taurus would ruin it. I would run 5w-30 in that Taurus all day long. I will not put 5w-30 in my truck unless it gets below 50 degrees. EVER. Because it would ruin my engine in my truck. Two different style engines, with two different build techniques.

The way engines were made changed in the 90's. So did the manufacturers recomendations to go along with it.

Modern oil tech is the same tech that reduced or eliminated zinc from modern oils, because modern engines with rollerbearing camshafts do not need it, and zinc is a factor in reducing catalitic converter lifespan. The same zinc that is needed on our older engines to keep the camshaft lobes from wearing flat. Newer modern oils are not friendly to our older engines at all. Why I use 15w-40 diesel oil. It's one of the few oils that still has some lubrication traits that our older engines need.

I'm not the only one who say's that. That is Fords recommendation for temperature range, not mine... but you do not have to take my word for it, look at the manual.

10w-30 Recomended for between -10F and 90F only.



You will never convince me that putting dirty oil from one engine into another is a good idea. Sorry.

It's a car built after 1990 as well. I wouldn't use a 10w30 in that car anymore than I would use a 5w-30 in my truck.

No, the purpose of the forum is to put out reliable information to help other people in need.

I have nothing against you personally, just your advice needs more thought and research as it's inaccurate in several ways.

 

There is nothing inaccurate about anything I have said here short of an exact comparision between viscosity and thickness, there I used simple common but not completely 100% accurate terms. It's not like 99% of people use the term viscosity in that manor or anything.

 

When you talk about or give advise about oil, you need to know the difference between newtonian and non-newtonian based oil as they react differently to flow, verses viscosity.

When you said...

... you were incorrect. Multigrade oils behave in a non-newtonian fashion. Even though the oil is thicker when it's cold, and thinner when it's hot, it's got the exact opposite viscosity properties, or exactly opposite of your statement above.

Single grade like SAE 30 behaves in a newtonian fashion, and would therfore behave like you stated above.

 

Now clearly your just arguing to argue.

Buddy your reading way too much into some article you found on the net, assuming much more then it implies, and being WAAAAYYYY to picky about exact terminalogy that your not even using correctly. ALL motor oils demonstrate non-newtonian properties, this does not make them "non-newtonian based oils" Nor does a non-newtonian fluid behave consistently as you seam to think, some flow rather well, some don't, some stir well, some don't. Non-newtonian simply refers to NOT-newtonian, as in NOT applying to the simple fluid flow models devised by Newton, few real world fluids are truely newtonian, incuding "single grade" oils and honey. Any fluid being non-newtonian is more a matter of degree then anything else, and really the term has more more to do with tricks sean on TV and YouTube then real fluid dynamics. In fact being non-newtonian is part of what makes a good oil.

The same can be said about the term "viscosity" there's how it's used in oil commercials and how it's used in the lab where often modified by another defining term like the ones I already mentioned; kinematic, centipoise, centistoke, shear, etc.

But does it really matter, nope, you go to the store, and you have a selection of motor oils to choose from. Your not engineering your own oil everytime you change it.

http://www.youtube.com/watch?v=3zoTKXXNQIU

 

I was going to say something...

 

I will agree with 81-F-150-Explorer here. My own 1985 Ford manual states the exact same information.

I agreed with this, too. And I just can't bring myself to argue oil weights with a man that has over 700,000 miles on his engine.

*****

On the other hand, I have also heard (and agree) with many of the statements Opossum has brought up in this discussion:

Taken from: http://www.bobistheoilguy.com/motor-oil-101/

"Confusion occurs because people think in terms of the oil thinning when it gets hot. They think this thinning with heat is the problem with motor oil. It would be more correct to think that oil thickens when it cools to room temperature and THIS is the problem. In fact this is the problem. It is said that 90 percent of engine wear occurs at start-up. If we are interested in engine longevity then we should concentrate our attention at reducing engine wear at start-up."

If I am understanding Opossum and the website above correctly, both 5W-30 and 10W-30 oils have the same thickness at operating temperature. The only time the 5W-30 oil is "thinner" than a 10W-30 oil is at cold ("W") start-up conditions where you need it to be "thin." This allows the engine to get quick oil flow when it is started cold verses dry running until lubricant either warms up sufficiently or is finally forced through the engine oil system. The advantages of a lower W viscosity number is obvious. The quicker the oil flows cold, the less dry running. Less dry running means much less engine wear.

Conclusions? The 5W-30 simply does not get as thick on cooling as the 10W-30, thus is better for your engine in colder temperatures and at start-up, where most of the engine wear occurs.

*****

Maybe Opossum and 81-F-150-Explorer are both correct. Were the oil standards somehow different in the 1980s when the Ford manual was produced compared to today's oil standards? This would certainly make sense, as today's oils are better than they were 20 years ago, and additive packages have certainly changed over years as the car engines have changed.

I personally use Motorcraft 5W-30 Synthetic Blend motor oil along with a Motorcraft FL-1A oil filter, as this is what my trusted ASE-certified mechanic told me to use when he rebuilt my engine last year, along with a bottle of ZDDPlus added to the engine oil at every change to protect the flat-tappet camshaft. Maybe that is what Ford tells mechanics to use these days, or maybe it is because he used a high pressure (not high volume) oil pump in my engine. At any rate, my engine seems to run fine with no leaks so far and with quick, high oil pressure at start-up and good oil pressure when hot. I live in South Carolina where temperatures reach close to 100 in the summer with very mild winters, and I only drive my truck 1-2 times a week.

I keep hearing and reading conflicting information on this issue, so I am not confident if I am using the correct engine oil weight for my truck or not. I hope I find out in this thread because I really respect both Opossum's and 81-F-150-Explorer's opinions.

 

Did I say that, NOPE could there be something better then regular 10W40 for that Ford now, YUP. I don't know, it's your truck, and you haven't told me much about it.
Already said that in MY posts above, all you have to do is read them. If that's not enough then clearly you have a computer with an internet connection, go find out for yourself.

But WE were asked by the OP, then I was asked for more from the OP, I answered and then defended my answer. Then YOU asked me, I gave and defended my answer. If you have a problem with that fine, but don't come at me like a moody woman who refuses to find out or think for herself cause I hurt your ego.


Edit, LMAO, I see you edited your post now.

 

Well, lets just say this argument has been going on since oil was invented.

Still trying to understand where you missed the part about the differences in oil and engines from 30 years ago til now.

 

Good stuff LARIAT 85, can't fault any of it and thanks for the backup/mediation, lol. Sounds like your all set, there might be a better oil, but can't fault it. And the ZDDPlus is a very good thing. My only concern for you I highlighted in red below.
Ya sure it's not the other way around, most engine builders go the other way, as do I. When it really comes down to it an engine doesn't need any more oil pressure then is needed to provide enough flow. So the only thing a high pressure pump does is put in a heavier pressure relief spring and bypass it less. While a high volume pump is actually larger and will ensure oil gets where it needs to go faster and maintain enough volume to maintain a more steady oil pressure.

 

I'm sorry isn't this a forum about 30 year old trucks, and can you go back in time and buy oil made 30 years ago?

 

There is no real need for a high pressure or high volume pump unless the clearances are wide. Stock pumps should provide all the pressure and volume required.

And here we get to flow through the bearings, etc.

Not enough flow and the bearings heat up. Too much flow and you build backpressure. This backpressure can break the pump and/or the shaft. This also increases the drag internal to the engine and reduced fuel efficiency.

A high volume pump bypasses more oil and heats the oil needlessly.

 

I buy the closest thing which is 15w40 refined for my diesel which has the extreme pressure additives.