Mobil 1 FS 5w40 at Walmart

Joined
Jul 2, 2009
Messages
1
Location
Central Valley, CA
Anybody having no luck finding Mobil 1 FS 5w40 At Walmart? Can’t seem to find them in Northern California. I know NAPA and Autozone sells them but Walmart sells them cheaper.
 
Joined
Dec 29, 2010
Messages
5,873
Location
Paramount, California
Anybody having no luck finding Mobil 1 FS 5w40 At Walmart? Can’t seem to find them in Northern California. I know NAPA and Autozone sells them but Walmart sells them cheaper.
Simply get the M1 FS 0W-40. M1 FS 5W-40 doesn't offer any advantages over M1 FS 0W-40. Base-oil (HTFS) and HTHS viscosities are about the same, and 0W-40 has more GTL. M1 FS 5W-40 is entirely redundant for any application—just a more cheaply made version of M1 FS 0W-40.

Base-oil viscosity (HTFS) and VII content of selected oils
 
Joined
Oct 7, 2012
Messages
926
Location
North Carolina
Lots of VeeDub and MB owners swear by 5W-40, plus it is less expensive than 0W-40

M1.2.jpg
 
Joined
Jan 25, 2003
Messages
5,349
Location
Decatur AL USA
Lots of VW and MB owners don't know ****.

Simply get the M1 FS 0W-40. M1 FS 5W-40 doesn't offer any advantages over M1 FS 0W-40. Base-oil (HTFS) and HTHS viscosities are about the same, and 0W-40 has more GTL. M1 FS 5W-40 is entirely redundant for any application—just a more cheaply made version of M1 FS 0W-40.

Base-oil viscosity (HTFS) and VII content of selected oils

Some owner's manuals recommend 5W-40 as an applicable grade but not 0W-40. That is an issue for some. If I wanted a 5W-40 I would likely get Castrol A3/B4 as it's cheaper locally and has LL-01 (Mobil 1 doesn't).
 
Last edited:
Joined
Dec 29, 2010
Messages
5,873
Location
Paramount, California
Some owner's manuals recommend 5W-40 as an applicable grade but not 0W-40. That is an issue for some. If I wanted a 5W-40 I would likely get Castrol A3/B4 as it's cheaper locally and has LL-01 (Mobil 1 doesn't).
This is a moot issue. As I said, the base-oil viscosity of M1 FS 0W-40 is not lower than that of M1 FS 5W-40. The same goes for HTHS. Unless the vehicle is in warranty, there is no problem with substituting 0W-40 for 5W-40 with these two oils for what the latter is recommended.
 
Joined
Jan 25, 2003
Messages
5,349
Location
Decatur AL USA
This is a moot issue. As I said, the base-oil viscosity of M1 FS 0W-40 is not thinner than that of M1 FS 5W-40. The same goes for HTHS. Unless the vehicle is in warranty, there is no problem with substituting 0W-40 for 5W-40 for these two oils where the latter is recommended.

Many people won't use a 0W in a car that specifies 5W. To me or you many products are likely redundant. Others don't have the same perspective.
 
Joined
Dec 29, 2010
Messages
5,873
Location
Paramount, California
Many people won't use a 0W in a car that specifies 5W. To me or you many products are likely redundant. Others don't have the same perspective.
If the base oil is of higher quality, a 0W-XX can be thicker than a 5W-XX in terms of both the base oil and HTHS. For example, if you look at my table linked above, Castrol 0W-40 A3/B4 is thicker than Castrol 5W-40 A3/B4. The same goes for high-quality synthetic 0W-20 oils—they can be thicker than conventional 5W-20 oils. For that reason, I wouldn't hesitate to substitute a synthetic 0W-20 where a conventional 5W-20 is recommended or a synthetic 5W-30 where a conventional 10W-30 is recommended.
 
Joined
Feb 6, 2021
Messages
1,024
Location
Massachusetts
Many people won't use a 0W in a car that specifies 5W. To me or you many products are likely redundant. Others don't have the same perspective.
I'd hope most people here understand oil viscosity enough to know 0w-40 and 5w-40 are equivalent at operating temperature. When it's cold as heck the 0w-40 is better.
 
Joined
Dec 29, 2010
Messages
5,873
Location
Paramount, California
I'd hope most people here understand oil viscosity enough to know 0w-40 and 5w-40 are equivalent at operating temperature. When it's cold as heck the 0w-40 is better.
Yes and no. A multigrade oil with a lower cold-viscosity rating can have a lower base-oil viscosity, which could result in more engine wear, as the engine wear is primarily dictated by the base-oil viscosity. However, for M1 FS 0W-40 and M1 FS 5W-40, the base-oil viscosity is about the same because the former's higher base-oil quality allows reaching SAE 40 viscosity without extra viscosity-index improver (VII). Therefore, it is more complicated than "You can always substitute a 5W-30 for a 10W-30" etc.
 
Joined
Jan 25, 2003
Messages
5,349
Location
Decatur AL USA
I'd hope most people here understand oil viscosity enough to know 0w-40 and 5w-40 are equivalent at operating temperature. When it's cold as heck the 0w-40 is better.

Most people just buy whatever is on the cap or in the manual (if they actually read it). If they do read the manual they panic because all they can find is SP and the manual specified some other Sx.
 
Top