Ultimate Motor Oil Thread or Why we hate CJ4/SM oils

[Trackrash]

I agree, at least in theory, 10-60 would be the best solution.

I would like to see a real comparison of Mobil 1 15-50, Brad Penn 20-50 and Porsche 10-60 where the cold and hot viscosities are measured.

[richardlw]

Originally Posted by kyngfish

I don’t understand the benefit of the high viscosity oils (20w50). Can someone sound off on why this would be desirable when starting up a cold car? I understand the 50 or even 60 weight portion when oil is warm. But not higher viscosity at cold temp.

Seems like it should be the other way around. Mcar consistently runs better on startup with the 15w oils than the 20w. And I have no proof, but I believe the brad penn was not a great idea in my 3.2. Now I’m considering going to the 10w options. Why would we want a thicker oil on startup?

20W-50 will cause more wear on every startup than 15W-50 or 5W-50. You need oil to circulate fast and build that cushion, splash around the valve train, etc.

Too many people use 20W-50, both for price and ignorance.

On the top end of the scale, the higher viscosities are needed in engines where they are run at high rpm. Almost any oil will work well up to about 2500 rpm, but the mineral oils will shear, so a 20W-50 mineral oil, at 4000 rpm is probably protecting like an xW-30, or maybe 40. A cheap synthetic will be closer to 50, and a good PAO/Ester blend will be protecting correctly. The higher the rpm, the more shear force.

[MrBonus]

Originally Posted by richardlw

20W-50 will cause more wear on every startup than 15W-50 or 5W-50. You need oil to circulate fast and build that cushion, splash around the valve train, etc.

Too many people use 20W-50, both for price and ignorance.

On the top end of the scale, the higher viscosities are needed in engines where they are run at high rpm. Almost any oil will work well up to about 2500 rpm, but the mineral oils will shear, so a 20W-50 mineral oil, at 4000 rpm is probably protecting like an xW-30, or maybe 40. A cheap synthetic will be closer to 50, and a good PAO/Ester blend will be protecting correctly. The higher the rpm, the more shear force.

I've always followed the chart in the manual which tells me 20W50 is good to below 20 degrees F. The odds of me ever driving my car below that are pretty much non-existent.

That said, I've considered switching to 15W50 but I'm probably just being pedantic with no tangible benefit.

[adias]

Originally Posted by richardlw

20W-50 will cause more wear on every startup than 15W-50 or 5W-50. You need oil to circulate fast and build that cushion, splash around the valve train, etc.

Too many people use 20W-50, both for price and ignorance.

On the top end of the scale, the higher viscosities are needed in engines where they are run at high rpm. Almost any oil will work well up to about 2500 rpm, but the mineral oils will shear, so a 20W-50 mineral oil, at 4000 rpm is probably protecting like an xW-30, or maybe 40. A cheap synthetic will be closer to 50, and a good PAO/Ester blend will be protecting correctly. The higher the rpm, the more shear force.

20W50 is fine unless you live in a very cold climate and drive the car below 30F. But, if you are worried about cold starts use a solid lubricant to continuously coat and remain on all moving parts. Liqui Moly MoS2 Anti-Friction Engine Treatment is the best there is. I have been using if for the last 2 years and the engine runs/starts smoother, meaning less friction.

[kyngfish]

Originally Posted by MrBonus

I've always followed the chart in the manual which tells me 20W50 is good to below 20 degrees F. The odds of me ever driving my car below that are pretty much non-existent.

That said, I've considered switching to 15W50 but I'm probably just being pedantic with no tangible benefit.

My experience is anecdotal and doesn’t qualify as data - but when I first got my car I bought the hype and got Brad Penn 20w50 and I swear to you it started burning more oil within 10k miles. Ever since I went to 15w50 delo and then 15w50 Mobil 1 - that oil burning acceleration has stopped. My car runs cooler as well. And I live in south Florida where it’s pretty much always at least 80. That’s why I’m now considering switching to the 10w60 liquid moly with the ceratec and seeing the difference. Honestly in 10-20 k im doing a top end anyway so I have zero to lose by testing it.

I’ve just always been curious why people keep recommending the 20 w xx oils when it seems to run counter to sense. But hey. I’m not an expert so I asked.

[adias]

Originally Posted by kyngfish

My experience is anecdotal and doesn’t qualify as data - but when I first got my car I bought the hype and got Brad Penn 20w50 and I swear to you it started burning more oil within 10k miles. Ever since I went to 15w50 delo and then 15w50 Mobil 1 - that oil burning acceleration has stopped. My car runs cooler as well. And I live in south Florida where it’s pretty much always at least 80. That’s why I’m now considering switching to the 10w60 liquid moly with the ceratec and seeing the difference. Honestly in 10-20 k im doing a top end anyway so I have zero to lose by testing it.

I’ve just always been curious why people keep recommending the 20 w xx oils when it seems to run counter to sense. But hey. I’m not an expert so I asked.

I do not think it is the 20W50 weight. I also saw significantly lower oil burning moving from Brad Penn 20W50 to Valvoline VR1 20W50. I am told it has to do with oil stocks.

I do agree that Brad Penn is much hyped. JMO.

[Steve@Rennsport]

Originally Posted by adias

I do agree that Brad Penn is much hyped. JMO.

I'd kindly suggest talking with professional engine builders who have inspected all the internals after long-term use before making blanket statements.

[HarryD]

Originally Posted by adias

I do not think it is the 20W50 weight. I also saw significantly lower oil burning moving from Brad Penn 20W50 to Valvoline VR1 20W50. I am told it has to do with oil stocks.

I do agree that Brad Penn is much hyped. JMO.

I have using Brad Penn in my 1973 almost since I got it in 2002 with 115000 miles. When I had an incident with the car at about 160000 miles, I needed to do a top end. Other than addressing the damaged parts, all my engine internals looked great with no unusual wear.

I will continue to use BP.

[MrBonus]

Originally Posted by kyngfish

My experience is anecdotal and doesn’t qualify as data - but when I first got my car I bought the hype and got Brad Penn 20w50 and I swear to you it started burning more oil within 10k miles. Ever since I went to 15w50 delo and then 15w50 Mobil 1 - that oil burning acceleration has stopped. My car runs cooler as well. And I live in south Florida where it’s pretty much always at least 80. That’s why I’m now considering switching to the 10w60 liquid moly with the ceratec and seeing the difference. Honestly in 10-20 k im doing a top end anyway so I have zero to lose by testing it.

I’ve just always been curious why people keep recommending the 20 w xx oils when it seems to run counter to sense. But hey. I’m not an expert so I asked.

It's wild how different these cars perform with different oils. While not a performance-related item, I found that my car runs cooler on Kendall than it did on Swepco. Neither ran hotter than they are supposed to but the temperature gauge stays slightly lower in all weather with Kendall.

[Reiver]

Originally Posted by Steve@Rennsport

I'd kindly suggest talking with professional engine builders who have inspected all the internals after long-term use before making blanket statements.

speaking of pro engine builders...some have mentioned adding LMoly MoS2 additive to oils for start up/etc. film protection....

Your opinion please and any other builders in the biz.... would you add tis to a 3 liter 911 system?

Why and/or why not.

[kyngfish]

Originally Posted by Steve@Rennsport

I'd kindly suggest talking with professional engine builders who have inspected all the internals after long-term use before making blanket statements.

Not to step on any toes - but it was an engine builder's comment on a thread here about cam wear on engines using brad penn that made me think twice, and also to ask the question I asked, because I don't think it's Brad Penn specifically. But people do talk about it like it's some kind of elixir. My belief was just that the 20w50 oils really aren't all that great.

My take - and my question - is why would we want an oil that's thicker at startup? The if the "20w" is due to the fact that the only way to get a higher warm viscosity, is by starting thicker, then I get it.

But now that even the Porsche Classic oil is 10w60, and liqui moly offers something similar, wouldn't having a lower weight oil be substantially better for your car? Especially if it's a car that sits a few days between drives?

Not trying to beat a dead horse, but because most wear happens on cold start, isn't it important?

[adias]

Originally Posted by kyngfish

Not to step on any toes - but it was an engine builder's comment on a thread here about cam wear on engines using brad penn that made me think twice, and also to ask the question I asked, because I don't think it's Brad Penn specifically. But people do talk about it like it's some kind of elixir. My belief was just that the 20w50 oils really aren't all that great.

My take - and my question - is why would we want an oil that's thicker at startup? The if the "20w" is due to the fact that the only way to get a higher warm viscosity, is by starting thicker, then I get it.

But now that even the Porsche Classic oil is 10w60, and liqui moly offers something similar, wouldn't having a lower weight oil be substantially better for your car? Especially if it's a car that sits a few days between drives?

Not trying to beat a dead horse, but because most wear happens on cold start, isn't it important?

I agree that there is no elixir. Zn/P can be replaced by better lubricants like Mo. Re 20W... these engines have higher tolerances (larger gaps) than modern engines, thus 20W cold is not as thick oil for them, as it would be for s tight modern engine. I too am planning to use a Liqui Moly oil because the germans use them with great results, but I am selecting Liqui Moly Touring High Tech 20W 50 and will add to that MoS2. I have been using MoS2 for the last 2 years, and the engine runs smoother and quieter.

[jlex]

Kyngfish asks a good question. Since most engine wear is supposed to occur at startup, I suppose a good oil for a car that's not driven very often should either leave a good coating of oil on wear components at last shut down, or be thinner at startup to help circulate the oil more quickly.
I'm using Valvoline VR1 20w-50 but am considering changing to Rotella T4 15w-50 thinking that thinner oil at startup is a better alternative (not to mention I can get it at about $3.25/qt.). The Rotella apparently has the Zinc & is a dino oil. My '88 has a totally dry engine, so switching to a synthetic at this point will probably cause it to start leaking (did that with my '88 Volvo & syn did cause it to leak until I switched back to dino oil)

[kyngfish]

Originally Posted by adias

I too am planning to use a Liqui Moly oil because the germans use them with great results,

When I wrote to Liqui Moly - I did ask them about the oil the recommend, and they recommended the 10w60 for my 3.2, but it's also pretty pricey. For me personally, it's a small price to pay. For what it's worth - I don't have any complaints about the 15w50 mobil1 i use now, the only reason I wanted to go to liqui moly was that - going back to my earlier question/comment, I believe 10w would be better for my car.

I was considering the MoS2 as well. They recommended the Ceratec, but I've seen threads where that stuff clogs up really small areas and I'm not sure I'm willing to try it on my engine yet.

[adias]

Originally Posted by kyngfish

When I wrote to Liqui Moly - I did ask them about the oil the recommend, and they recommended the 10w60 for my 3.2, but it's also pretty pricey. For me personally, it's a small price to pay. For what it's worth - I don't have any complaints about the 15w50 mobil1 i use now, the only reason I wanted to go to liqui moly was that - going back to my earlier question/comment, I believe 10w would be better for my car.

I was considering the MoS2 as well. They recommended the Ceratec, but I've seen threads where that stuff clogs up really small areas and I'm not sure I'm willing to try it on my engine yet.

You can use 10W60. I Think though that for older engines 20W50 makes more sense.

Ceratec is for new alloy engines. Do not use Ceratec on a 3.2 - use MoS2.

[schoward]

Originally Posted by jlex

Kyngfish asks a good question. Since most engine wear is supposed to occur at startup, I suppose a good oil for a car that's not driven very often should either leave a good coating of oil on wear components at last shut down, or be thinner at startup to help circulate the oil more quickly.
I'm using Valvoline VR1 20w-50 but am considering changing to Rotella T4 15w-50 thinking that thinner oil at startup is a better alternative (not to mention I can get it at about $3.25/qt.). The Rotella apparently has the Zinc & is a dino oil. My '88 has a totally dry engine, so switching to a synthetic at this point will probably cause it to start leaking (did that with my '88 Volvo & syn did cause it to leak until I switched back to dino oil)

I have watched and debated internally if to make any change. Been using 15w40 Shell Rotella T / T4 Dino for last several years which can be had at criminally low prices from Kmart or Amazon. Engine temps never too hot even in summer with AC on, and very consistent low burn rate and car running fantastic on it. And light enough weight that I can feel reasonably ok starting the car in 20 degree January to drive kids to school. Last I checked, Rotella seems to sneak in with just enough zddp levels.

My rebuilder specified Mobil 1 15w50 after my top end (following break in) many years ago. To me, this is a great choice for synth. But my recent shop for last 10 years says go Dino for what I have (a stock SC with a few minor oil weeps). Two very reputable porsche shops that i used prior to my top-end always dunked 20w50 Dino in it. One other used Valvoline 15w40 dino. That was before the whole zddp hysteria.

Have debated stepping up to VR1 20w50 in summer but outside of the zddp level comfort, not much motivation to do so given the experience with Rotella above. I will say my high school hopped up Chevy Nova did great on the Valvoline Racing VR1 20w50 (black bottle back then circa 1991). Great product also.

[Reiver]

schoward…. I'm liking Joe Gibbs Driven 15w-50...a good alternative...not cheap but not Porsche 10-60 prices.

[adias]

Originally Posted by Reiver

schoward…. I'm liking Joe Gibbs Driven 15w-50...a good alternative...not cheap but not Porsche 10-60 prices.

Some say that Porsche Classic 10W60 is Castrol 10W60 European Version.

[seafood10]

I have used Brad Penn with great results but am always open to new suggestions from you helpful gentlemen!

[chuckr]

I switched from Brad Penn 20/50 to Driven 15/50 last year. My 3.2 did not really burn any Brad Penn, usually had a quart or two left over before an oil change. No leaks at all. Same for the Driven. No usage, no leaks,runs at same temp as always. I changed oil at 5000 miles with Brad Penn. I decided to go 7000 with the Driven to try and offset the price.