0w-40

dawudih · 07-11-2011, 09:42 PM

why is mobil 1 0w-40 not labeled energy conserving on the api starburst? all the other weights of mobil 1 are. the engine starts up alot quieter & less harsh sounding in the morning with this oil.

secondnissan · 07-12-2011, 03:53 AM

because at operating temp the "40" weight oil is much thicker then a "30" or "20" weight oil. The second number in Xw-XX is the viscosity at 212 degrees . 40 will protect the engine better at oil temps above 230 but will hurt fuel economy.

dawudih · 07-12-2011, 08:36 PM

Than why are the 10w-40 & 15w-50 energy conserving? They should be thicker than 0w-40...

Methodical4u · 07-12-2011, 10:17 PM

Amsoil SSO 0w-30 baby!

corner3garage · 08-03-2011, 01:23 PM

Quote:

Originally Posted by dawudih

why is mobil 1 0w-40 not labeled energy conserving on the api starburst? all the other weights of mobil 1 are. the engine starts up alot quieter & less harsh sounding in the morning with this oil.

The engine also starts up a lot quieter mostly because the oil is a lower viscosity when the oil is cold. This gives more cold protection since the oil is thinner at startup, but as the it warms up it also gives the thicker 40 viscosity protection.

-Mike

dawudih · 12-17-2012, 06:31 AM

Just drained my Mobil 0w-40 out after 8k miles & 10 months. Hated to do it because it still looked clean & clear. I really think European formula oils are much better than regular synthetics. Also use it in my 4Runner with 185k miles & looked good after 10k & 8 months.

07-11-2011, 09:42 PM	#1 (permalink)
dawudih Base Member Join Date: Mar 2011 Location: Katy, TX Age: 49 Posts: 93 Drives: 2011 370z auto Rep Power: 14	0w-40 why is mobil 1 0w-40 not labeled energy conserving on the api starburst? all the other weights of mobil 1 are. the engine starts up alot quieter & less harsh sounding in the morning with this oil.

12-17-2012, 06:31 AM	#6 (permalink)
dawudih Base Member Join Date: Mar 2011 Location: Katy, TX Age: 49 Posts: 93 Drives: 2011 370z auto Rep Power: 14	fyi Just drained my Mobil 0w-40 out after 8k miles & 10 months. Hated to do it because it still looked clean & clear. I really think European formula oils are much better than regular synthetics. Also use it in my 4Runner with 185k miles & looked good after 10k & 8 months.

07-12-2011, 03:53 AM	#2 (permalink)
secondnissan Base Member Join Date: May 2011 Location: chicago burbs Posts: 70 Drives: 10 370z 7at Rep Power: 13	because at operating temp the "40" weight oil is much thicker then a "30" or "20" weight oil. The second number in Xw-XX is the viscosity at 212 degrees . 40 will protect the engine better at oil temps above 230 but will hurt fuel economy.

07-12-2011, 08:36 PM	#3 (permalink)
dawudih Base Member Join Date: Mar 2011 Location: Katy, TX Age: 49 Posts: 93 Drives: 2011 370z auto Rep Power: 14	Than why are the 10w-40 & 15w-50 energy conserving? They should be thicker than 0w-40...

07-12-2011, 10:17 PM	#4 (permalink)
Methodical4u A True Z Fanatic Join Date: Jun 2011 Location: Maryland Posts: 1,393 Drives: 11 370 6mt pw w/sp Rep Power: 15	Amsoil SSO 0w-30 baby!