Originally Posted By: dnewton3
Originally Posted By: pops91710
By
full I meant
all synthetic and not blended with dino oil. I think the main reasons we used synthetics in the USAF was the heat factor. I was told by the jet boys it was better in jets due to their high temperatures. I never meant to imply that what works in a jet works well in an automobile. They are two different animals with two diffrent purposes and two different appetites. So, what was your viscosity recommendation since that what my original question was all about?
First - welcome to the site
Next - you've got a lot of comments and Qs in this one thread, so I'll tackle them in no particular order.
As for the comments above, regarding "full synthetics" and "not blended with dino oil" I have some news for you. Any PAO based lube is going to have some portion of conventional oil in it; there is no "pure" (100%) PAO lube in the general automotive market. They use the convention oil to hold the additives in suspension because, while PAOs do a great job of resisting oxidation and holding vis, they do a poor job of holding additives. Just so you know; I'm not aware of any brand of auto-market PAO that is not a "blend" of many things, just like all other brands/grades.
That being said, you can also quit worrying about what was good in the USAF and air-based mechanical stuff. While very important in that arena, and some of those lessons may loosely be relevant for stuff here on the ground, it's just too much of a leap to think all things will translate equally. Leave those assumptions behind.
As for the grade (viscosity) for the mod motors (4.6L, 5.4L, 6.8L) I've seen far more data than most here, and I can say that generally the grade used (5w-20, 5w-30, 10w-30, 10w-40) does not seem to have much affect on wear rates. These motors generally wear very well, and are not particular to grade preference; at least not nearly as much as their owners are ...
I presume your 6.8L F-series has the typical liquid/liquid oil cooler on it. As I recall, Ford used a liquid-to-liquid cooler in the return water line on those engines, if I'm not mistaken.
Does not really matter what the ambient temps are to a large degree. AS long as your cooling system (water pump, radiator, t-stat, etc) are in good shape, then your oil temp is going to be fairly consistent because your coolant will be fairly consistent. Your oil temps will be controlled fairly well by the coolant side of things. Certainly, on a really hot day, up a long pull, with a heavy load, you'll see an increase in temps. But just remember that 250degF is a very safe and normal temp for conventional lubes. That is a target temp that many, many SAE tests are run at for hours on end. I can assure you that your oil sump temp it not that hot all the time. If you're getting high coolant or oil temps, the very first thing to look at is the "stack" (the combo of coolers in the front of your truck, including a/c condensor, radiator, supplemental tranny cooler, etc). With the age of your truck, restriction of airflow is THE number one thing that affects cooling. Road pebbles, dead bugs, tiny bits of road tar, etc all take their toll over time.
Of the stuff you mention, I don't recall you stating what your OCIs are. If you intend anything close to "normal" (less than 10k miles), the mod motors just don't really care. I realize you state you're hauling a heavy load and do mountains a lot (I've actually been out in some of the areas you speak of on my RV trips as well). These 6.8L engines are made to pull loads; they are under-square but rev decently. While it may seem atrocious to rev an engine to 5000 rpm, you're not really hurting it. Sure - it will suck fuel down like a college kid drinks grain-based carbonated refreshments, but that does not mean things are being hurt in the engine.
You may be seeing a bit of oil consumption; with the miles on your rig that would not be unexpected. A grade change may help out here, or it may not. Depends on WHERE the oil is being consumed. Using a thicker lube to reduce consumption is a stop-gap measure. It only puts off the issue; it does not fix a root cause. If your valve-stem seals are worn, no oil it going to fix that. Etc.
I have a recommendation for you: TEST STUFF!
Use your rig with a decent 5w-20 or 5w-30; anything you prefer. Then get a UOA. You can compare/contrast that data to macro-market info. They try something else, and UOA again. Eventually you'll likely find that it does not matter nearly as much to your engine as it does to your ego and wallet. Try a 5w-20 syn. Try a 10w-30 syn. Try a 5w-30 dino. Do some self-testing and see how much or little it affects wear. I think you'll be surprised. Don't worry about what goes into the bottle; no engine has ever been saved by a label. Rather, focus on results; see what comes out of the crankcase. Test several products in your application and then draw a conclusion based on facts; don't rely on mythology and rhetoric.
Start here:
https://bobistheoilguy.com/used-oil-analysis-how-to-decide-what-is-normal/
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Very concise and informative response!
First, I don't know why anyone would get the impression I am
worried about oils used in the USAF. It was just a reference to what I learned while serving as a flightline airmunitions specialist. Until automotive syns got popular and affordable, I never thought of those USAF syns.
Second, I have full confidence in my V10. One, I studied them thoroughly before I took the plunge. I'll admit at first I was shy of hitting 5K rpm's. When I had my Gear Vendor Over drive unit installed I expressed my concerns back in 20to the company's head engineer there in El Cajon. He said I'll bet you are a 460 man. I said how diod you know? And yes I have had several 460s. He said let that engine wind, it can do 5 grand all day long (if you have to fuel capacity!!) I have been towing now since 1981. My truck is my third Triton and second V10 and 5th and best TV of all previous ones.
I have not been much in the past with experimentation. Once I found something I would stick with it. Like Ford Trucks. Never had any other brand and see no reason not to change there! But lately I am starting to look around and try some new things with regards to passenger cars and motor oils. I'm really interested in Pennzoil's Platinum series synthetic made from natural gas.
As for my temps, so far the truck runs as cool as it ever has. That's another thing that has impressed me. I have a digital monitor plugged in to my OBD2 port that gives me read outs of intake temp, throttle position, rpm,coolant temp, etc. The truck just hasn't shown any systems degradations yet. Ford keeps sending those "come on down!" emails and I just tell them they make them too well and mine still is in top condition.
Mythology is why I am here. I don't by into the popular shade-tree stuff. I have been following this site for about ten years gleaning what I could from it.I think I started that when I was looking into Mobil I and Amsoil.
Thank's for your tips and counsel and your non-condecension. It was refreshing.
PS- If there are any mistakes here its because my eyesight is kinda blurry. I had eye surgery Thursday. Just to get my eyelids pulled back up....the shades were too low.
