Am i the only person with a love for Sae 40 SG monograde? My preferred choice for quietening and limiting oil consumption on older vehicles.
SAE 40
- Thread starter Matt97
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I think in the right climate, that's the bomb. But there's such a limited market for it, it's hard to brew it and distribute it.
Personally, I'ma dyin' for a 20w-30 that perfectly suits my climate, my (not really that much) older cars. Virtually no VIIs, robust oil. Shell is now making a T-6 15w-40; I'd love to see a 15w-30 or narrower viscosity spread so I can trust it.
Personally, I'ma dyin' for a 20w-30 that perfectly suits my climate, my (not really that much) older cars. Virtually no VIIs, robust oil. Shell is now making a T-6 15w-40; I'd love to see a 15w-30 or narrower viscosity spread so I can trust it.
JHZR2
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There's a huge market for it in HD engines, especially marine.
Lack of trust of 15w-40 grades sounds like speculation to me... 15w-30 oils do exist, I have a few gallons of Delo.
The use situation has to be correct for a straight weight.
Lack of trust of 15w-40 grades sounds like speculation to me... 15w-30 oils do exist, I have a few gallons of Delo.
The use situation has to be correct for a straight weight.
I have sae30 in my tractor. Thinking a 40 would be next.
If you're out from under your warranty and you *can* run a mono grade because your ambients rarely drop below 0c, do it. You might take a little hit in the mpg's due to oil drag but a mono grade like a SAE30 or 40 is going to provide superior wear protection at operating temp when compared to a multi vis.
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It's changing over time: Mobil and Castrol have some strong 15W40's we run in CAT mid sized marine engines
Mid-sized being 7K HP in that world with 440 gallons each, also not a huge capacity relative to others …
https://www.exxonmobil.com/en/marine/Products/Categories/List/mobilgard-engine-oil-benefits
Mid-sized being 7K HP in that world with 440 gallons each, also not a huge capacity relative to others …
https://www.exxonmobil.com/en/marine/Products/Categories/List/mobilgard-engine-oil-benefits
South Africa, summer temps 28deg C to mid 30's, winter around the low 20's. I find using it in older cars works very well.
Old engines thrive on mono grades. Especially air cooled ones. A carb'ed engine should be considered "severe conditions" Thick oil is the best for fuel dilution. It is silly to try to wring the last erg of efficiency out of an engine that wasn't designed to that spec. I don't endorse high fuel
il 2 stroke mix ratios either
il 2 stroke mix ratios either
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15w40 is the kind of spread they can use something like EHC65 thereby minimizing VM …
That's an inexpensive base stock and HDEO with a 10 Noack (
why I don't get "synthetic" HDEO when pour point is not an issue
That's an inexpensive base stock and HDEO with a 10 Noack (
why I don't get "synthetic" HDEO when pour point is not an issue
Mono grades are very old school. Go ahead and use them but have a look at the websites for Shell Rotella and Mobil Delvac. These are sites for long haul truckers and owners of serious heavy equipment. It's all multigrade. No need to go back to the 60's.
I use it on high mileage older vehicles that call for a 20w50 SF/SG grade. Really quietens them up.
Not brand specific, just use from the major players.
Not brand specific, just use from the major players.
I ran SAE 30 and SAE 40 in my 97 V6 Chevy pickup for years. I did this because I got a bunch of it almost free. It performed perfectly! My son still drives the truck today with near zero consumption.
Originally Posted by gfh77665
I ran SAE 30 and SAE 40 in my 97 V6 Chevy pickup for years. I did this because I got a bunch of it almost free. It performed perfectly! My son still drives the truck today with near zero consumption.
My first car, growing up in Socal, I ran a straight SAE 30. Wasn't until I got an IROC that I ran a multi vis and that was a 10w30. Loved that car right up to the point of wrapping it around a light pole....«
I ran SAE 30 and SAE 40 in my 97 V6 Chevy pickup for years. I did this because I got a bunch of it almost free. It performed perfectly! My son still drives the truck today with near zero consumption.
My first car, growing up in Socal, I ran a straight SAE 30. Wasn't until I got an IROC that I ran a multi vis and that was a 10w30. Loved that car right up to the point of wrapping it around a light pole....«
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I've run SAE 40 and heavier(up to SAE 50) in my old sloppy British stuff in the summer, especially when I've been trying to fight oil consumption(fortunately fixed in the MG for now with a repacked oil mist separator). Considering that 20W-50 is what's specced year round, that's not too much of a stretch.
VR-1 is my go-to monograde
VR-1 is my go-to monograde
Originally Posted by Matt97
Am i the only person with a love for Sae 40 SG monograde? My preferred choice for quietening and limiting oil consumption on older vehicles.
You are in the minority that is certain. Even 40 grades around here are API SN.
Am i the only person with a love for Sae 40 SG monograde? My preferred choice for quietening and limiting oil consumption on older vehicles.
You are in the minority that is certain. Even 40 grades around here are API SN.
Originally Posted by Snagglefoot
Mono grades are very old school. Go ahead and use them but have a look at the websites for Shell Rotella and Mobil Delvac. These are sites for long haul truckers and owners of serious heavy equipment. It's all multigrade. No need to go back to the 60's.
I thought the old Detroits didn't do well on 15W40? Something about them made it shear the oil down.
Originally Posted by Matt97
Am i the only person with a love for Sae 40 SG monograde? My preferred choice for quietening and limiting oil consumption on older vehicles.
Dumb question: those older engines, how hot did the oil in them run? No coolant-oil heat exchanger. Big engine, lots of surface area. Usually not operated under a load. Does the oil stay relative cool? Wondering if it thus stays thick, thus quiet (taking up clearance or adding mass to anything tapping away).
Mono grades are very old school. Go ahead and use them but have a look at the websites for Shell Rotella and Mobil Delvac. These are sites for long haul truckers and owners of serious heavy equipment. It's all multigrade. No need to go back to the 60's.
I thought the old Detroits didn't do well on 15W40? Something about them made it shear the oil down.
Originally Posted by Matt97
Am i the only person with a love for Sae 40 SG monograde? My preferred choice for quietening and limiting oil consumption on older vehicles.
Dumb question: those older engines, how hot did the oil in them run? No coolant-oil heat exchanger. Big engine, lots of surface area. Usually not operated under a load. Does the oil stay relative cool? Wondering if it thus stays thick, thus quiet (taking up clearance or adding mass to anything tapping away).
Yep, thats the main reason. I dont do it on newer vehicles with extended drain and specific synthetic requirements.
Duron SAE 40 in my 2011 Duramax LML right now. P 1200, Zn 1300 BN 8.5
Delo 100 SAE 40 has the same additive package as their 5W40 pcmo 5W40. (not the watered down Euro-Dexos offering)
Delo 100 SAE 40 has the same additive package as their 5W40 pcmo 5W40. (not the watered down Euro-Dexos offering)
What does the factory call for on the Duramax and has the use of a 40 oil made any difference to the engine, ie noise or cooling reduction?
My first, a 2006 LBZ listed 15W40 as first choice above zero F, 5W40 below that. SAE 10W30 and SAE 30 were also listed as optional grades.
As the power and torque were both raised in the LML, the 10W30 and SAE 30 options were no longer listed in the owners manual.
My latest, a 2018 L5P with higher torque and horsepower again only lists 5W40 and 15W40, CJ-4 or CK-4.
The old warning about 10W40 still lingers on, despite there being a few synthetic CK-4 and CJ-4 offerings.
(Just like the wrong end of the spare tire crank photo and the transmission fluid change interval.)
If you look at base oil viscosity (BOV), SAE 30 is thicker than 5W40, and therefore offer better protection to the loaded (top) con-rod bearing.
If you buy into that, then SAE40 should protect better than 20W50.
Throw out the SAE grades and go with Shannow"s XW/HTHS.
That translates to pick your ambient and your engine's HTHS requirement.
Your engine oil choice must meet both at the end of the oil drain interval.
What does Dr Noack have to say about SAE40? Chevron publishes their group II of the viscosity applicable at 4%.
As the power and torque were both raised in the LML, the 10W30 and SAE 30 options were no longer listed in the owners manual.
My latest, a 2018 L5P with higher torque and horsepower again only lists 5W40 and 15W40, CJ-4 or CK-4.
The old warning about 10W40 still lingers on, despite there being a few synthetic CK-4 and CJ-4 offerings.
(Just like the wrong end of the spare tire crank photo and the transmission fluid change interval.)
If you look at base oil viscosity (BOV), SAE 30 is thicker than 5W40, and therefore offer better protection to the loaded (top) con-rod bearing.
If you buy into that, then SAE40 should protect better than 20W50.
Throw out the SAE grades and go with Shannow"s XW/HTHS.
That translates to pick your ambient and your engine's HTHS requirement.
Your engine oil choice must meet both at the end of the oil drain interval.
What does Dr Noack have to say about SAE40? Chevron publishes their group II of the viscosity applicable at 4%.
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