Mobil1 15w50 experiment

O.K. Fact check. 2001 is supposed to have an LS motor with roller cam. If you lobes are wiped, the rollers are shot and no oil is going to help. You don't see the cam with the intake off. There is a bolt on valley tray under the intake. So what engine is this?

If you want to run a bit thicker HD oil I might suggest Rotella T4 10W30 or better yet
the latest Quaker state 10W30 synthetic is a good oil with good cold weather properties.

Nothing to learn with a 15W50, Just that you made a mistake by running it in anything other than an air cooled bike.
Underneath the intake there is a plate with a gasket. That was leaking oil so I replaced that gasket when I did intake. When you pull that plate you can see the cam
 
I'm surprised no one has mentioned this, but the "horrible GM gauges" likely include a dummy gauge for the oil pressure, so whatever readings you're getting from that are probably not worth a whole lot of your attention.

I know Mazda started using dummy gauges back in the early 90s, I'd be surprised if GM wasn't using them in 01.

I have coolant temp, oil pressure, and voltage gauges on my 16 Silverado, and none of them relay accurate information.
 
I'm surprised no one has mentioned this, but the "horrible GM gauges" likely include a dummy gauge for the oil pressure, so whatever readings you're getting from that are probably not worth a whole lot of your attention.

I know Mazda started using dummy gauges back in the early 90s, I'd be surprised if GM wasn't using them in 01.

I have coolant temp, oil pressure, and voltage gauges on my 16 Silverado, and none of them relay accurate information.
Oh yes they are horribly inaccurate. All gm gages I've seen of the late 90s to mid 2000s are.
 
This is not an experiment - no controls - no KPI’s - no measurements …
Want thicker all season M1 oil ? Buy 0W40 …
I've always been one to say that, (and who knows. This may be dated information) but that Mobil 1 0W-40 as well as 15W-50 may very well be their "best" oils.

The 15W-50 just might bring up some compression in some poorly sealing cylinders, mechanics always did say to use thicker oil in worn or tired engines... now, how they got that way, I don't know.

How well do your rings seal? What is your compression? What is it wet (with a small amount of oil in cylinder) and dry?

Oh yes they are horribly inaccurate. All gm gages I've seen of the late 90s to mid 2000s are.
Idiot lights with gauges.. calibrated to read in the middle on a WIDE variety of pressures. Baseline it 5W-30 to 20W-50, you "likely" we'll have the oil pressure go up only very little or at all according to that gauge on the thicker stuff...
 
Drove the 2008 yaris for 1st time with the 15w50 this morning. Coldest morning of the year so far. 33f fired up just as fast as the 5w40 in summer Temps. Wich surprised me. This car doesn't have temp or oil pressure gauges so no idea of what's different there. Honestly 0 difference felt between this oil and the5w40. I felt a much bigger difference in the k1500. 0 vvt stumble no vvt codes. Will see as it gets colder
 
Drove the 2008 yaris for 1st time with the 15w50 this morning. Coldest morning of the year so far. 33f fired up just as fast as the 5w40 in summer Temps. Wich surprised me. This car doesn't have temp or oil pressure gauges so no idea of what's different there. Honestly 0 difference felt between this oil and the5w40. I felt a much bigger difference in the k1500. 0 vvt stumble no vvt codes. Will see as it gets colder
At 33F that probably should not be surprising. It would help to learn what the winter rating means and does not mean, and when it means it.
 
At 33F that probably should not be surprising. It would help to learn what the winter rating means and does not mean, and when it means it.
He‘ll know at zero … Batteries are not cheap these days … Undue stress with no gain …
 
I'm on an experiment too I guess. My usual oil is m1 0w40 fs but none on sale when I needed it for my latest oil change on the 2005 Silverado 4.8. 233k miles 10k hours.

Switched to Pennzoil euro LX 0w30. Oil pressure slightly lower on torque pro, maybe slightly quieter. It feels like it gained a significant amount of power which could be a combination of the temperature drop lately, atmospheric conditions, lighter oil, maybe others factors also or none of the above.

Not scientific. The only thing i know is power is up. A steep uphill on ramp to the highway I merge at around 70mph with the truck fully loaded with surveying equipment and iron. I'm getting an extra 5mph after full throttle from a stop to the end of the on ramp.

We'll never know the truth though with these "experiments".
 
He‘ll know at zero … Batteries are not cheap these days … Undue stress with no gain …

no experience with 0 F.

But at +12 F I had no starting issues with my ‘66 Ford Galaxie 500 starting up as usual with the M-1 15w-50. Appeared to start as normal. Mea Culpa; just was lazy enough not to change oil for a more winter friendly lubricant. Now using M-1 0w-40 year round in several different vehicles, classic and modern.

The car has the usual Ford FE engine, 390 cubic inch & A/T.

The OP’s car might be a different animal. Especially with cam issues.

Z
 
At 33F that probably should not be surprising. It would help to learn what the winter rating means and does not mean, and when it means it.
I believe it was CATERHAM who said at 35F the difference between 0W, 5W and 10W the difference was negligible. 15W and 20W might show a slight difference.
 
I would love to see you do a uoa with this oci. All the years I used M1 15W50 in my 300ZX, I never thought to do a uoa.
 
Drove the 2008 yaris for 1st time with the 15w50 this morning. Coldest morning of the year so far. 33f fired up just as fast as the 5w40 in summer Temps. Wich surprised me. This car doesn't have temp or oil pressure gauges so no idea of what's different there. Honestly 0 difference felt between this oil and the5w40. I felt a much bigger difference in the k1500. 0 vvt stumble no vvt codes. Will see as it gets colder
I did a freezer test many years ago with M1 15W50 and RP 20W50. The M1 shook around in the bottle as if it were at room temperature, while the RP was almost solid as super thick gear oil and would barely slosh around.

I remember MJ (the tech guy at Exxon Mobil) had told me that M1 15W50 silver cap (back when it first came out in the early 2000s) was a group IV/V oil. Whether it still is, is anyone's guess.
 
I did a freezer test many years ago with M1 15W50 and RP 20W50. The M1 shook around in the bottle as if it were at room temperature, while the RP was almost solid as super thick gear oil and would barely slosh around.

I remember MJ (the tech guy at Exxon Mobil) had told me that M1 15W50 silver cap (back when it first came out in the early 2000s) was a group IV/V oil. Whether it still is, is anyone's guess.
Maybe I should do a freezer test between the 15w50 and the t6 5w40. See if I could post a video of it. What is approximate cost for Blackstone uoa?
 
Switched to Pennzoil euro LX 0w30. Oil pressure slightly lower on torque pro, maybe slightly quieter. It feels like it gained a significant amount of power which could be a combination of the temperature drop lately, atmospheric conditions, lighter oil, maybe others factors also or none of the above.

Not scientific. The only thing i know is power is up. A steep uphill on ramp to the highway I merge at around 70mph with the truck fully loaded with surveying equipment and iron. I'm getting an extra 5mph after full throttle from a stop to the end of the on ramp.

We'll never know the truth though with these "experiments".
Very much correct.
 
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Maybe I should do a freezer test between the 15w50 and the t6 5w40. See if I could post a video of it. What is approximate cost for Blackstone uoa?
Why not learn about the details of the tests in SAE J300 instead? They are what lead to the oil‘s winter rating. That test is actually representative of the real-world behavior of oil at low temperatures, whereas the freezer test has little or nothing to do with how it behaves in an engine. Neither does a UOA.

People on here are always wanting to throw away actual, relevant and substantive information for a parlor trick or state fair demonstration.
 
The freezer tests and oven tests, etc, are purely for fun. But I did find it surprising how solid the RP was coming out of the freezer, and it was said (by RP) to be a pao.
 
Maybe I should do a freezer test between the 15w50 and the t6 5w40. See if I could post a video of it. What is approximate cost for Blackstone uoa?
The only thing about that is that a freezer test has entertainment value not scientific value as it is not about scientific test and you would be going to project Farm route and people may need you with consternation, at least on here.

Now if you put a see-through oil pan on your car and did a video of starting it in temperatures such as that where @OVERKILL lives.... you would be a hero.
 
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