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expired Posted by Corwin | Staff • Sep 9, 2021
expired Posted by Corwin | Staff • Sep 9, 2021

1-Gallon Castrol Assuron HD Diesel SAE 30 Motor Oil $8.04 + Free S&H w/ Walmart+ or orders $35+

$8.04

$20

59% off
Walmart
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18 Comments

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Sep 9, 2021
1,539 Posts
Joined Jul 2006
Sep 9, 2021
Analog
Sep 9, 2021
1,539 Posts
Good deal if you don't need multi-vis. My truck needs multi-vis due to the climate 4-seasons I encounter.
Sep 9, 2021
309 Posts
Joined Apr 2016
Sep 9, 2021
fantastic84
Sep 9, 2021
309 Posts
I THINK this might be rated for Off road use only?
Sep 9, 2021
22 Posts
Joined Nov 2018
Sep 9, 2021
BBartow
Sep 9, 2021
22 Posts
Good for the mower
Sep 9, 2021
1,281 Posts
Joined Sep 2018
Sep 9, 2021
gathermewool
Sep 9, 2021
1,281 Posts
No ILSAC rating or API seal (old CF diesel rating is old). Not meant for motor vehicles. I'd say this is only good for Outside Power Equipment (OPE)
1
Sep 9, 2021
59 Posts
Joined Mar 2008
Sep 9, 2021
rogo178
Sep 9, 2021
59 Posts
Great oil to run on a generator in warm climate
Sep 9, 2021
245 Posts
Joined Mar 2009
Sep 9, 2021
coffeecandy
Sep 9, 2021
245 Posts
I have a tire machine that requires 30w oil, will this work?
Sep 9, 2021
15,688 Posts
Joined Nov 2010
Sep 9, 2021
80is
Sep 9, 2021
15,688 Posts
perfect for frying eggs
1
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Sep 9, 2021
2,247 Posts
Joined Sep 2003
Sep 9, 2021
Boink
Sep 9, 2021
2,247 Posts
There's nothing like a quart of motor oil to get things moving after you've been bound up! #constipation
1
Sep 9, 2021
7,417 Posts
Joined Nov 2006
Sep 9, 2021
KMan
Sep 9, 2021
7,417 Posts
Generally speaking, what makes motor oil suitable for diesel engines as opposed to gas ones, for the same weight and type? Is this mostly marketing?
Sep 9, 2021
752 Posts
Joined Nov 2005
Sep 9, 2021
Archimedes001
Sep 9, 2021
752 Posts

Our community has rated this post as helpful. If you agree, why not thank Archimedes001

Quote from KMan :
Generally speaking, what makes motor oil suitable for diesel engines as opposed to gas ones, for the same weight and type? Is this mostly marketing?
API C service category (CK-4, CJ-4 etc.) has a completely different set of engine test specifications than an API S category (SP, SJ, etc.) for passenger cars.

What this means is the formulations are similar but diesel spec engine oils tend to have a lot more dispersant in there to handle soot and also usually higher ZDDP (antiwear) and detergents. They also tend to use a different type of viscosity modifier (usually a styrene type) that helps disperse soot and also has a really good shear stability as the drains on diesel oils is very long.

You could technically use a diesel spec oil in a passenger car as it is over formulated for those but... the drawback is if they have a high ZDDP level which could cause premature catalytic converter failure.

The other way around doesn't work, a passenger car oil couldn't survive in a diesel engine for a very long time. For a short period sure but not for the drains and the amount of soot those engines see.

That said this stuff is API CF-2, CF so it's old spec probably use it for lawn mowers or other random applications but not a modern passenger car or even a modern diesel.

Oh should also add that even modern CK-4 diesel oils do not have to pass the low-speed-preignition (LSPI) test so they might use all calcium based detergent systems which could be disastrous for your turbo GDI engines (VW, Ford ecoboost, etc.)
Last edited by MrMotorOil September 9, 2021 at 08:54 AM.
2
1
Sep 9, 2021
177 Posts
Joined Jul 2011
Sep 9, 2021
BlluittFW
Sep 9, 2021
177 Posts
Quote from KMan :
Generally speaking, what makes motor oil suitable for diesel engines as opposed to gas ones, for the same weight and type? Is this mostly marketing?
From what I've read is that the diesel formulations have higher zinc compound concentrations for increased anti-wear of the metal parts in the engine, but catalytic converters can't handle that higher concentration (sounds like it would clog them up early) so that's why it's not recommended for gas cars with cats.

I run the diesel version it in my outdoor gas engines - mower, tractors, etc since they don't have emissions / cats.

This is cheaper than the TSC jugs I buy so will grab a couple of these.
1
Sep 9, 2021
7,417 Posts
Joined Nov 2006
Sep 9, 2021
KMan
Sep 9, 2021
7,417 Posts
Quote from MrMotorOil :
API C service category (CK-4, CJ-4 etc.) has a completely different set of engine test specifications than an API S category (SP, SJ, etc.) for passenger cars.

What this means is the formulations are similar but diesel spec engine oils tend to have a lot more dispersant in there to handle soot and also usually higher ZDDP (antiwear) and detergents. They also tend to use a different type of viscosity modifier (usually a styrene type) that helps disperse soot and also has a really good shear stability as the drains on diesel oils is very long.

You could technically use a diesel spec oil in a passenger car as it is over formulated for those but... the drawback is if they have a high ZDDP level which could cause premature catalytic converter failure.

The other way around doesn't work, a passenger car oil couldn't survive in a diesel engine for a very long time. For a short period sure but not for the drains and the amount of soot those engines see.

That said this stuff is API CF-2, CF so it's old spec probably use it for lawn mowers or other random applications but not a modern passenger car or even a modern diesel.

Oh should also add that even modern CK-4 diesel oils do not have to pass the low-speed-preignition (LSPI) test so they might use all calcium based detergent systems which could be disastrous for your turbo GDI engines (VW, Ford ecoboost, etc.)
Quote from BlluittFW :
From what I've read is that the diesel formulations have higher zinc compound concentrations for increased anti-wear of the metal parts in the engine, but catalytic converters can't handle that higher concentration (sounds like it would clog them up early) so that's why it's not recommended for gas cars with cats.

I run the diesel version it in my outdoor gas engines - mower, tractors, etc since they don't have emissions / cats.

This is cheaper than the TSC jugs I buy so will grab a couple of these.
Thanks, very detailed and informative. The only part I don't get is why this would affect the cat, since the oil is supposed to remain in the engine block. Are we talking blow-by and oil leakage into the combustion chamber, that over time affects the cat?
Sep 9, 2021
3,248 Posts
Joined Jul 2013
Sep 9, 2021
madmax718
Sep 9, 2021
3,248 Posts
Straight 30 diesel is often the speced oil for standby machinery that is stored in conditioned space, such as sheltered diesel generators and fire pumps.
It's also commonly speced on older farm equipment.
Sep 9, 2021
3,248 Posts
Joined Jul 2013
Sep 9, 2021
madmax718
Sep 9, 2021
3,248 Posts
Quote from KMan :
Thanks, very detailed and informative. The only part I don't get is why this would affect the cat, since the oil is supposed to remain in the engine block. Are we talking blow-by and oil leakage into the combustion chamber, that over time affects the cat?
Diesel rated oils often has wear additives that are really helpful to recent wear. The same additives are useful in flat tappet cam motors, and also very good for metal to metal wear. Additives such as zinc, and molybendium can damage some platinum catalytic converters.
1

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Sep 9, 2021
752 Posts
Joined Nov 2005
Sep 9, 2021
Archimedes001
Sep 9, 2021
752 Posts
Quote from KMan :
Thanks, very detailed and informative. The only part I don't get is why this would affect the cat, since the oil is supposed to remain in the engine block. Are we talking blow-by and oil leakage into the combustion chamber, that over time affects the cat?
There is a small amount of oil and components that is burned off (cylinder wall residual oil) as the engine runs, this includes metal ash such as the phosphorus component of ZDDP which then deposit on the face of the catalytic converter and eventually coat it so that it runs below the threshold of the 02 sensors and bam check engine light.

Additive companies already make a low volatility ZDDP but even those still have a small percentage that volatilizes. So yes you're right it's just oil that somehow finds it way out of the engine sump.
Last edited by MrMotorOil September 9, 2021 at 11:11 AM.

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