Oil Viscosity upgrade for old V10?

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Hello Memebers! This is my first post here, so bear with me. I have long been an avid fan of two fully synthetic oils; Mobil One and Amsoil which I have used exclusively in my 2003 F250 Superduty with a 6.8L V10. For my last four oil changes I have dropped using the Amsoil brands strictly because I can buy the 5 quart jugs at Walmart for far less money per quart than the six requisite quarts of Amsoil, not to mention the added shipping costs.

I use the truck often in the warmer time of year to tow a big 5th wheel trailer through hot deserts and high mountain passes and I will regularly hit 3,500 to 4,500 rpm for long stretches of desert grades throughout the Mojave, Nevada, and Utah deserts often in temps of 114 degrees. Rarely do I hit 5 grand rpms but it has been known to happen ascending 9% grades (or more) between Cedar City, Utah
and Duck Creek, Utah Topping out well over 9,000 ft elevations.

I'm giving you all this background information to ask one simple question. My odometer has just passed 100,000 miles. I'm getting ready to make several camping road trips and am wondering if I should stay with the factory recommended viscosity of 5W-20? I just changed the oil last week and used the Mobil 1 gold label 5W-20 Extended Performance oil. However, given the fact my engine has now 100k on it, I am wondering if I should use from now on their Mobil 1 5W-20 High Mileage Advanced Full Synthetic Motor Oil? OR----should I just move one step up to a higher viscosity —say 5W-30? Yes, it is using some oil now between changes unless I don't tow on some road trips. I'd say it uses about 1 qt to every 1 K miles which isn't all that bad given the thrashing that engine takes.

Comments, opinions, and experiences will be appreciated.
 
Originally Posted By: Olas
For towing at 114 degrees I'd use Maxlife 5w30 in that application.


Thanks, Olas. I used to be a big Valvoline fan. However, I would prefer to stay with Mobil's full syn. Valvoline is a blend. Bear in mind my local temps here are rarely over 104 and usually never exceeed 100. Nevertheless, your suggestion on viscosity is worth considering in any climate given the number of miles logged. 114 is often along the Las Vegas, Nevada to St. George, Ut stretch of the I-15 which is appx 137 miles. Thankfully my engine seldom exceeds 214-216 degress for very short periods. The heavy duty cooling system is very efficient.

(Manchester, eh? My grandmother was from east of you in coastal Grimsby.)
 
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You can get the Maxlife in "Full Synthetic" too. Please spend some time here and see what that term really means with the two oils being discussed. Most readily available oils aren't what you might assume they are.

What kind of fuel economy are you seeing with that V10? I'm just curious and want to compare with my PSD.
 
I'm more prone to believe Amsoil is a full synthetic from what I have read here over the years. I have heard that Mobil 1 wasn't a true full synthetic, but Mobil disputes that. Apparently for a short time they were not making a full synthetic after the ravages to their plant by a hurricane (Katrina?). Honestly I have favored Amsoil, but now I am retired I'm watching my spending. I only change oil twice a year since the truck sits parked for months at a time, so I could afford to go back to Amsoil should the need prove itself. In the USAF we used synthetics in our jet engines and only changed the oil after SOAP sample returns required it. It's the reason why I believe in synthetics and I served back in 1967 thru 1973 long before syns became popular in the automotive industry.

You are right, however. The evolution of synthetic automotive engine oils may not match that of aviation development, although the founder of Amsoil claims his does.

My fuel economy varies according to terrain, locality, and fuel blends. Generally, while not towing, on long highway trips I can get as much as 15 mpg. Since nearly all my driving is from coastal California to mountainous Utah, in other words: all "uphill" 12 or 13 is more common. Winds are a pain and will drop it to 11 mpg.Once I top out in Cedar City and cruise mostly flat in double overdrive to Salt Lake City, it comes back up to 15 plus. Unless I am towing in hot weather I will use regular gasoline. It's the California pump prices that kills my CPM. Once out of Kalifornia, who cares? The fuel prices drop 75 to 95 cents per gallon less, and sometimes $1.00!

Towing? OOOOOFFF! When I tow from my home to my camping spot 69 miles away at 7,000 ft elevation, uphill grades ALL the way I get 6mpg, unless mama wants her cast iron cooking skillets, etc then I get 5mpg. From here to Las Vegas I'll get 7 to 8. Needless to say I do need to fill up in LV! 8mpg has been my best, but that is almost never. Don't forget I have 4.30 axles. I used to have 3.73 but they proved unworthy with my newer 5th wheel. I added a Gear Vendor to compensate so I can over drive in any forward gear, even in factory O/D.

Here's the thing, I look at over-all costs. Aside from brakes, tires, shocks, and scheduled maintenance I have spent nothing on repairs with the exception of upper ball joints, a Ford failure, in my opinion. Everything on it is original save what I have noted in custom gearing, etc. Is it cheaper to operate than I diesel? I have no idea. I'm extremely impressed with the V10, but my next will be a diesel or nothing at all. I don't like the gasoline options Ford now offers. The V8 is close to my V10 in output, but I want something more nesxt time. Problem is, can I afford it?
 
Originally Posted By: pops91710
I'm more prone to believe Amsoil is a full synthetic from what I have read here over the years. I have heard that Mobil 1 wasn't a true full synthetic, but Mobil disputes that. Apparently for a short time they were not making a full synthetic after the ravages to their plant by a hurricane (Katrina?).


None of that makes sense. If you are referring to the argument about Group III synthetics being "true synthetics", then you should know that Amsoil uses Group III in their synthetic products. Good Group III synthetic base stocks have similar, identical or even superior properties when compared to properties of PAO. ExxonMobil demonstrated that years ago with their Visom product. ExxonMobil uses a blend of base stocks in their products but like most producers does not divulge the details. If one wishes to try and read the tea leaves of MSDS however, it appears that some of their products (especially 0W-40) is currently composted of a percentage of of PAO. However, it is also true that when they moved away from Visom it lost Longlife-01 certification. Whether that is significant no one knows, but (apparently) the European Visom-based product still has Longlife-01. It becomes pointless to try and predict the performance of a synthetic motor oil based on "Group".

Katrina disrupted only some synthetic base stocks. The production of 0W-40 with Visom was not affected.
 
Thank you for the detail in your response about your fuel economy. My 6.4 will get 8mpg towing a 9000lb tandem axle toyhauler through the California hills, and 10-11 towing responsibly on flat ground. Given my maintenance and repairs you should definitely be operating at a lower cost than I am. Though there is something to be said for the fun of having 490hp and 960ft/lbs available when wanted. My effective rear axle ratio is 3.22:1 with the tires I'm running.

At work I have a 2015 F350 with a service body and the 6.2 gas engine. It is horrible. I came from a 2001 Chevy 3500 Duramax with an even heavier service body on it. I want it back. The 2015 is gutless, always at least one gear too high, and averages 8.8mpg as displayed on the info center.
 
Also, the comparison between turbine aircraft oils and automotive engine oils isn't very meaningful. People who know a lot more about it than I do can give better details, but the operating environment and the objectives of the oils aren't the same. For example, I don't think the finished turbine oils have any metallic additives. This makes the chemistry quite different between the two.

For the most part aviation (especially general aviation) is backwater compared to the rest of the world. Just because it is used on an airplane doesn't make it "better" by a long stretch. Automotive oil technology is very advanced.
 
Yeah, Thanks for the info on the towing mileages. Ive been wanting a 99-03 SD with the V10. I can't afford the maintenance costs on newer diesel and the prices of 7.3L trucks is WACK!! I very familiar with the mod motor and so it just makes the most sense to me.

I agree with the Maxlife Syn 5W30. You also might consider a 40 grade, like Castrol or Mobil 0W40 or one of the diesel 5W40s.

Jim: Your work should have ordered a F450; then the gas engine would be a 6.8L V10.
 
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Moving up one step may not be adequate, I would've moved up 2 steps to an xW40 in your applications ......
without an iota of doubt.
Oil consumption of 1 quart per k miles in a 100k engine is simply alien to my countrymen.
 
Originally Posted By: zeng

Oil consumption of 1 quart per k miles in a 100k engine is simply alien to my countrymen.


Mine too. Havn't used quarts since primary school arithmetic class sometime in the early '60's.
 
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At minimum, move to the HM oil, IMO. But I'm on the side of the thicker crowd in this case. At 100k miles, there is zero reason that could convince me to stay with a 20 weight, especially towing a TT in hot weather.
Back then, rumors ran the full gambit from "smaller oil passages" and "tighter clearances" to "she'll blow up if you use a thicker oil!" on the later model Triton's. If you looked at part numbers comparing the 1999 I had then and the "new" 5w20 versions in 03 and on, there was no changes made to the motors, period.
I ran 10w30's for the most part, dual rated diesel oils. And that's what I say for you as well.
Stay with M1 if you like, but you'll get excellent performance, quite likely better UOA's, and a thicker oil film that will protect in heat if you switch to a 10w30 syn blend like Rotella, Valvoline Premium Blue or Delo. But I only got 150k out of mine before I moved to a diesel, so I could be wrong. I still see the truck occasionally, rusted as heck but ticking along 7 years after I sold it.
 
Here in the USA we still use quarts, only slightly less than a liter which measures 33.8 ounces. Sorry, you'll just have to figure out what that means in metric.
 
Originally Posted By: Ducked
Originally Posted By: zeng

Oil consumption of 1 quart per k miles in a 100k engine is simply alien to my countrymen.


Mine too. Havn't used quarts since primary school arithmetic class sometime in the early '60's.


Here in the USA we still use quarts, only slightly less than a liter which measures 33.8 ounces. Sorry, you'll just have to figure out what that means in metric.
 
Originally Posted By: Jim_Truett
Thank you for the detail in your response about your fuel economy. My 6.4 will get 8mpg towing a 9000lb tandem axle toyhauler through the California hills, and 10-11 towing responsibly on flat ground. Given my maintenance and repairs you should definitely be operating at a lower cost than I am. Though there is something to be said for the fun of having 490hp and 960ft/lbs available when wanted. My effective rear axle ratio is 3.22:1 with the tires I'm running.

At work I have a 2015 F350 with a service body and the 6.2 gas engine. It is horrible. I came from a 2001 Chevy 3500 Duramax with an even heavier service body on it. I want it back. The 2015 is gutless, always at least one gear too high, and averages 8.8mpg as displayed on the info center.


I have been wanting that kind of power also, but I go into shock everytime I see those window stickers. My BIL pays $1,000 a month for his financing. NO WAY!
 
Originally Posted By: kschachn
Originally Posted By: pops91710
I'm more prone to believe Amsoil is a full synthetic from what I have read here over the years. I have heard that Mobil 1 wasn't a true full synthetic, but Mobil disputes that. Apparently for a short time they were not making a full synthetic after the ravages to their plant by a hurricane (Katrina?).


None of that makes sense. If you are referring to the argument about Group III synthetics being "true synthetics", then you should know that Amsoil uses Group III in their synthetic products. Good Group III synthetic base stocks have similar, identical or even superior properties when compared to properties of PAO. ExxonMobil demonstrated that years ago with their Visom product. ExxonMobil uses a blend of base stocks in their products but like most producers does not divulge the details. If one wishes to try and read the tea leaves of MSDS however, it appears that some of their products (especially 0W-40) is currently composted of a percentage of of PAO. However, it is also true that when they moved away from Visom it lost Longlife-01 certification. Whether that is significant no one knows, but (apparently) the European Visom-based product still has Longlife-01. It becomes pointless to try and predict the performance of a synthetic motor oil based on "Group".

Katrina disrupted only some synthetic base stocks. The production of 0W-40 with Visom was not affected.


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?
 
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?


I was only responding to your post:

Quote:
I'm more prone to believe Amsoil is a full synthetic from what I have read here over the years. I have heard that Mobil 1 wasn't a true full synthetic, but Mobil disputes that. Apparently for a short time they were not making a full synthetic after the ravages to their plant by a hurricane (Katrina?).


As much as Amsoil is a "full synthetic" so is Mobil 1 and it always has been. Nothing changed in that regard post-Katrina. Mobil 1 was never blended with dino oil, ever.

As for what viscosity you should use, what does your owner's manual say? Chemistry I understand a bit but I am in no way skilled enough to recommend any oil other than what the manufacturer of the vehicle requires or recommends. The point of your post may have been for grade recommendations but you also posted what I quoted and my response was about that.
 
They are both good oils. 100,000 miles though and the clearances have opened up a wee bit, so xW-40 is entirely appropriate.

Any oil on the Porsche A40 list should be fine. They have high HP density and plenty of heat concerns, so their testing is in line with what you put your truck through ...

OTOH, I'd be plenty comfy with Valvoline full synthetic (or NAPA equivalent). I'd also be very comfy with a synthetic HDEO in xW-40 for the summer pulls
smile.gif


You have an oil cooler and you transfer some of the eat to the cooling system directly so I'd be paying serious attention to that side.
 
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