SM/GF-4 VS. SL/GF-3

[MADMIKE]

Is the new SM/GF-4 DEFINITELY a better oil than the outgoing SL/GF-3? Is it at least as good or better in all respects? Does the reduced phosphorous content compromise the anti-wear performance of the oil or are they using another anti-wear substitute that adequately compensates for the reduced protection? Is it improved in some ways but not as good in others? Just wondering if I should be using the GF-4 as soon as I can find it or sticking with the GF-3 as long as it's available. Thanks!

 

[Ken2]

Yes, better oil.

These are the standards for the oil:
http://www.infineum.com/information/api-passenger-sm-2004.html
http://www.infineum.com/information/api-passenger-sj-sl-2004.html

In some cases the individual tests for SM were changed because the testing equipment was no longer available. In other cases the tests were changed to better reflect the desired goals. EPA always wants cleaner emissions and lower lube oil consumption. The oil and additive companies aways want cheaper oil and cheaper testing. The car companies always want longer oil drain intervals and cleaner engines & lower wear, mainly for the lease customers who return cars that didn't get regular oil changes.


Ken

 

[MADMIKE]

Thanks Ken!

 

[farrarfan1]

A slight concern I've had is the SM GF-4 Mobil 1 5W30 does not carry the A5 rating that the SL GF-3 did. The 10W30 does. I've seen several discussions on here that some members think the old SL formula was/is better than the new SM.Since I decided to start using Mobil 1 5W30 I'm not sure which is better.I currently have a case of the new 5W30 and a case of the new 10W30. Will probably put in the 10W30 the first of April and see how things develop with the 5W30.