0-40 vs 5-40 vs 10-40 M1 in Arizona

[sjpitts]

Ok, I just spent some time reading all the "what oil" to use threads. I am looking for oil for my 93 FZJ80, with 138k miles on it. Based on what Cary (resident oil expert) said, I went looking for 5-40 or 10-40 Mobil 1.

I can't find any.

I did however, find 0-40 in quart containers at wally world. I don't know about this zero weight oil, it makes me nervous. Is there any downside to using a 0-40 oil in Arizona?

This truck is not likely to see even "cool" weather for six months, and instead will likely be used to tow my boat in 110 degree temperatures (hence the desire for 40 weight, instead of the 5-30 I did find).

Jared

Better yet: Anybody know of a source of 10-40 or 5-40 M1 in Arizona?

 

[Rich]

If I were towing a boat in Arizona, during the summer, which, as a matter of fact, I have done, but not with a cruiser, then I would use M1 15w50, which, in fact, I did.

 

[Tools R Us]

M1 15W-50 is in my rig. Looking at the AU chart, 15W is good to 14F, how many times in the oil's life do you expect to run in less than 14F? For the next 6 months sub 100F days will be rarer than 110F+ days, combining that with towing I would run the 15W-50.

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AU viscosity from Andrew at 80school
1fzfe motor
20w50 oil- -7 deg to 38 plus ; 19 f to 100 f
15w40 oil -10 deg to 38 plus; 14 f to 100 f
10w30 oil -18 to +38 deg; 0 f;to;100 f
5w30 -30 to 8 deg celcius ; -22 f to 46 f

 

[sjpitts]

M1 15W-50 is in my rig. Looking at the AU chart, 15W is good to 14F, how many times in the oil's life do you expect to run in less than 14F? For the next 6 months sub 100F days will be rarer than 110F+ days, combining that with towing I would run the 15W-50.

--------------------------------------------------------------------------------

AU viscosity from Andrew at 80school
1fzfe motor
20w50 oil- -7 deg to 38 plus ; 19 f to 100 f
15w40 oil -10 deg to 38 plus; 14 f to 100 f
10w30 oil -18 to +38 deg; 0 f;to;100 f
5w30 -30 to 8 deg celcius ; -22 f to 46 f

50! That is getting up there. I hadn't really considered using 50. Where do you find M1 15-50? I don't think I have seen that either.

But does anybody have answer to my original question. Is there a downside to going beyond the range you need (0-40) when a smaller range (10-40) would do? I know they have 0-40 at wally world. I don't remember seeing 15-50 anywhere.

Jared

 

[tarbe]

Or just get Mobil Delvac 1 or Truck & SUV 5W-40. My Wal-Mart (and most I've been in) sell the latter.

They also sell Rotella 5w-40 in the blue bottle, a decent Group III oil for about $15/gallon.

 

[Bear80]

I liked using the M1 15w-50 here in south texas, however I'm giving Castrol syntech 5w-50 a try this summer. But I have yet to run a full tank yet and now it's down for a birfield job. I would like to see if my gas mileage, idle, oil leaks change at all, but mostly I didn't like the near $7 price of the M1 vs. $5 for the syntech.

Also you might not have noticed the M1 15w-50 because it is now part of the "extended" mileage oil, so it may be off to the side from the other M1 oils.

 

[Tools R Us]

50! That is getting up there. I hadn't really considered using 50. Where do you find M1 15-50? I don't think I have seen that either.

I got it at wallyworld, IIRC ~$25 a gal.

But does anybody have answer to my original question. Is there a downside to going beyond the range you need (0-40) when a smaller range (10-40) would do? I know they have 0-40 at wally world. I don't remember seeing 15-50 anywhere.

Jared

I got my truck a couple of years ago on July 4th, it had 5W-30 in it from a recent Lexus dealer change. At idle when warm the oil gauge would hardly move above the lower line, when cruising it was close to the second line, less than a third of the way up. With the 15W-50 it idles at the 1/3 mark and cruises at the 2/3 mark.

The oil recommended by Toyota in the USA is distorted by politics, I prefer to use the foreign recommendation. Many have run the US recommended oil and gotten good wear numbers in testing, but I'm not sure how well they would do in our climate with hard driving, wheeling, towing tossed in?

When testing the A/C last year I twice measured 125F+ setting in traffic. With that kind of temps likely I prefer to have the margin in oil viscosity at the top end of the scale, so I use the lowest temp expected as the selecting point. Also Mobil oils run on the thin side of the scale.

 

[tarbe]

But does anybody have answer to my original question. Is there a downside to going beyond the range you need (0-40) when a smaller range (10-40) would do?
Jared

Assuming basestocks with the same viscosity index, the narrow range oil will require fewer (less) viscosity index improvers, VII.

Fewer VII, while still achieving the required viscosity for you application, is always better than more. VII are polymeric molecules than can and do shear under the stresses found in an internal combustion engine. So a 0W-40 will not stay in grade as well as a 10W-40, again, assuming equivalent VI in the basestock...the 0W will have more VII in it, which is prone to shearing.

How much that will matter in most cases is debatable. We are splitting some hairs here. The 1FZFE is not a particularly fussy engine when it comes to oil.

 

[sjpitts]

Assuming basestocks with the same viscosity index, the narrow range oil will require fewer (less) viscosity index improvers, VII.

Fewer VII, while still achieving the required viscosity for you application, is always better than more. VII are polymeric molecules than can and do shear under the stresses found in an internal combustion engine. So a 0W-40 will not stay in grade as well as a 10W-40, again, assuming equivalent VI in the basestock...the 0W will have more VII in it, which is prone to shearing.

How much that will matter in most cases is debatable. We are splitting some hairs here. The 1FZFE is not a particularly fussy engine when it comes to oil.

So I guess you saying that the narrower range oil will last longer. Right? So if you can get 7k out of 10-30, you might only get 5k out of 10-40 and 3k out of 0-40 before it breaks down? Is that a fair assesment of the issue?

I think I remember hearing this explanation before, but for some reason I thought that this was only really an issue with dino oils, and that synthetic oils are engineered from the ground up to have a certain range-- and hence the addition of "improvers" is not really an issue in synthetics.

Not true? How much of an issue is it in synthetics? The same as with Dino's?

Jared

 

[MaddBaggins]

I'm using Chevron Delo 400 15w40. Autozone has it for about $8 a gallon. It's dino oil and I change about every 2500 to 3000 miles. I gave up using M1 because I can't let it go past 3k, and that was getting expensive.

 

[Gauge]

Well - given the tendancy of my rig to have almost zero oil pressure at idle (when the oil is hot), I am thinking of running 20-50 or something MUCH thicker than I am running now. 15-50 at a minimum.

 

[cary]

Assuming basestocks with the same viscosity index, the narrow range oil will require fewer (less) viscosity index improvers, VII.

Fewer VII, while still achieving the required viscosity for you application, is always better than more. VII are polymeric molecules than can and do shear under the stresses found in an internal combustion engine. So a 0W-40 will not stay in grade as well as a 10W-40, again, assuming equivalent VI in the basestock...the 0W will have more VII in it, which is prone to shearing.

How much that will matter in most cases is debatable. We are splitting some hairs here. The 1FZFE is not a particularly fussy engine when it comes to oil.

This is not a valid arguement anymore. VII improvers and the base oils are radically better than they were 10+ years ago. You cannot make any conclusion about an oils ability to stay in grade based on its weight span. In the case of Mobil 1, their Supersyn VII improver has a VI measured in the 1000's, 10x greater than any past VI improver.

You comment about the 80 being easy on oil is spot on. There have been quite a few UOA's of this engine now and its design and oil capacity have shown it to be very easy on oils. Even in an Arizona climate, there is no need to run more than a 40 weight oil unless you are running a turbo or running the motor under very heavy throttle for extended periods in 100F+ temps, and even then it is just adding to the margin of safety. Run the Mobil 1 0w-40 and don't worry about it. If you have consumption issues or just want to save some money, use the Shell Rotella Synth 5w-40 from Walmart for $15 per gallon. Either will run just fine in your engine for 7500-10,000 mile intervals.

 

[tarbe]

So I guess you saying that the narrower range oil will last longer. Right? So if you can get 7k out of 10-30, you might only get 5k out of 10-40 and 3k out of 0-40 before it breaks down? Is that a fair assesment of the issue?

I think I remember hearing this explanation before, but for some reason I thought that this was only really an issue with dino oils, and that synthetic oils are engineered from the ground up to have a certain range-- and hence the addition of "improvers" is not really an issue in synthetics.

Not true? How much of an issue is it in synthetics? The same as with Dino's?

Jared

There is more to how long an oil "lasts" than just staying in grade, although viscosity is arguably the single most important property. And your examples of mileage to breakdown are way too severe against the 0-40, assuming similar basestocks.



I really think you'll be fine with any API SL or SM 0W-40, 5W-40 or 10W-40 synthetic oil. I run 5W-30 group III most of the time in Houston and have fine reports (got a couple hundred quarts at half-price on a closeout and could not resist!). These engines generally do quite well on dino, for that matter. I would be using dino in Houston if it were not for the great deal I got on the Group III synthetic.

 

[tarbe]

Well - given the tendancy of my rig to have almost zero oil pressure at idle (when the oil is hot), I am thinking of running 20-50 or something MUCH thicker than I am running now. 15-50 at a minimum.

15W-50 and 20W-50 are the same viscosity at operating temperature (ie, both are a 50wt). The 15W-50 will exhibit better flow at low temps.

You really don't need much oil pressure at idle.

 

[tarbe]

VII improvers and the base oils are radically better than they were 10+ years ago.

I am sure that is true. I am also sure that I continue to read reports of Mobil 1 0W-40 thinning more than expected.

I don't use it myself, so only have the data that others present to go on. But test data means more to me than the starting VI - I am sure you agree.

 

[cary]

I think the shearing issue of M1 is massively overstated. In a few motors (mostly turbos and that Ferrarri 328 that seems to shear everything) there has been some shearing. The wear numbers haven't shown adverse results and even though people on BITOG like to complain about it, it still remains the factory fill choice and recommended oil for AMG, Porsche, Austin Martin, and others.

 

[tarbe]

I think the shearing issue of M1 is massively overstated.

You have to remember, these same guys go ballistic when Amsoil thickens a half a centistoke! So at least they (we) are consistent

 

[Tentsontop]

I've played with just about all the M1 synthetic oils. The only vehicle I've noticed a difference with is my bike. I'm running the 15-50 red cap in it and it shifts better than it did with dino. I run Dino+MOA in all my cars now.

 

[rgsiii]

Mobil 1 Truck & SUV 5W-40 has been discontinued according to the Mobil site. I used it with good sucess. The Truck & SUV oil is now a 5-30 weight oil.

There is a new Mobil 1 Turbo Diesel Truck 5W-40 oil and I don't know the API ratings--could be the same oil. It is not available to me in BFE, Mississippi.

My local Wally World only has the new Mobil 1 T/S formulation. I am going to try the Rotella T synthetic. No other source here sells synthetic in any form other than the quart.

How does the Amsoil XL-7500 10-40 compare to others? I would likely order a 30-55 gal container. Since this would be a couple of years worth of oil, how well does oil store?

 

[Mike S]

Silly me, I'm just running syn of the weight suggested by the factory manual. Why should I do something different?

M