: 5w30 or 0w30



ThumperPup
08-03-09, 12:13 AM
I'm just curious here i know that my Seville was designed for 5w30
but what would happen if i switch to 0w30
i use a mobile one full syn 5w30 and i was thinking of switching to the mobile one fuel saving full synthetic wich not sure if it is a box hoxe on weather it will really do anything or not but i was thinking about changing to the 0w30 they use for the formula
is this a good idea or no

Submariner409
08-03-09, 09:14 AM
The "fuel saving" difference between the two oil grades is slim and none. You will NEVER see a bit of difference. Maybe if you lived near Dkoz in Alaska with his extended nights and sub-zero starts, but 5W-30 is perfect for your Ohio car. Would you see any cost savings by switching to Pennzoil Platinum 5W-30 synthetics ?? Look on the oil shelf next time you're in the store.

Ranger
08-03-09, 10:43 AM
On the other hand........... I still use 10W30.

ThumperPup
08-03-09, 10:56 AM
The "fuel saving" difference between the two oil grades is slim and none. You will NEVER see a bit of difference. Maybe if you lived near Dkoz in Alaska with his extended nights and sub-zero starts, but 5W-30 is perfect for your Ohio car. Would you see any cost savings by switching to Pennzoil Platinum 5W-30 synthetics ?? Look on the oil shelf next time you're in the store.

i see penzoil platnium is cheaper the the mobile one i use but i never liekd penzoil i know when it comes down to oil brands its all about prefrances and what you like
thanks for the help on this i am going to stick with 5w30

i was wondering sometimes i go downt o texas and FL for the winter spend a month down there are a time
should i switch to a diferantw W oil when i go down to the hotter areas ?

ThumperPup
08-03-09, 10:57 AM
On the other hand........... I still use 10W30.


what does 10w30 do that 5w30 i never really understood the weights of the oils and what oil you use in what area
could you please explain

Ranger
08-03-09, 11:08 AM
The first number is the cold viscosity (thickness). The second is the viscosity after it is warmed up. The theory is that 5W flows better when cold. While that is true, I have never had any problem with 10W. 5 just seems to thin to my liking. I once asked our old Guru about it and without actually saying it, he kind of admitted that if GM had it's way, they'd probably have stayed with 10w. 5 was to placate the treehuggers.

Bottom line is in real cold areas -20f and lower you want the lower 5w's. I've even started at -27f with 10w and never had a problem.

ThumperPup
08-03-09, 04:17 PM
so in ohio in the summer should i switch to 10w or should i stay at 5w
im still a bit confused or could i do damage if i swithced back and forth like in the summer if i use 10W and in the winter go to 5w

Submariner409
08-03-09, 06:51 PM
Your owner's manual clearly gives the "GM preferred" oil viscosity of 5W-30, with a secondary OK for 10W-30 if the lowest temperatures anticipated is what ??? 32 degrees ?? Look at the graph - it's in the book!

If GM says you can run 5W-30 all year in a 2000+ engine, why go through the unnecessary drill of changing oils every October and May ???

Ranger is correct also - running 10W-30 quality oil year-round will hurt nothing, especially if the car is garage-kept. You WILL have slower cranking speeds and lower oil flow COLD at very low temperatures - that's the nature of the beast.

I have the same engine as you, for all practical purposes, and I'll be damned if I'm going to obsess over a 5W- difference in cold oil flow characteristics. I run 5W-30 year-round and the Northstar engine loves it, and I drive the absolute snot out of it. Heck, man, my Ford truck runs 5W-20 year-round and I just finished a 1,400 mile round trip to SC and back and did not use one drop of oil. This isn't the old days - modern lubricants are truly miraculous in their "oily" abilities.

ThumperPup
08-03-09, 07:12 PM
Your owner's manual clearly gives the "GM preferred" oil viscosity of 5W-30, with a secondary OK for 10W-30 if the lowest temperatures anticipated is what ??? 32 degrees ?? Look at the graph - it's in the book!

If GM says you can run 5W-30 all year in a 2000+ engine, why go through the unnecessary drill of changing oils every October and May ???

Ranger is correct also - running 10W-30 quality oil year-round will hurt nothing, especially if the car is garage-kept. You WILL have slower cranking speeds and lower oil flow COLD at very low temperatures - that's the nature of the beast.

I have the same engine as you, for all practical purposes, and I'll be damned if I'm going to obsess over a 5W- difference in cold oil flow characteristics. I run 5W-30 year-round and the Northstar engine loves it, and I drive the absolute snot out of it. Heck, man, my Ford truck runs 5W-20 year-round and I just finished a 1,400 mile round trip to SC and back and did not use one drop of oil. This isn't the old days - modern lubricants are truly miraculous in their "oily" abilities.


ok well thank you very much for the info i hope i didnt upset you by askig such a stupid question
i will stick to 5w30

i know fords dont use oil at all hardly
i had my old Lincoln 2000 continental
i could drive like 4k before it would start using any oil
in this seville i had a quart of oil like eveyr 1500 miles if im lucky soemtiem i hav eot do it evyer 1200 miles

Submariner409
08-04-09, 12:31 PM
Not a stupid question........and your Northstar oil consumption falls within the original Cadillac curve for "acceptable oil consumption", and you're not alone in the 1,500 mile/quart range, either.

Keep your oil level at halfway up the dipstick mark - at the top is overfilled, and the engine will burn off the extra half quart quickly. A recent GM TSB on this.

ThumperPup
08-04-09, 04:54 PM
Not a stupid question........and your Northstar oil consumption falls within the original Cadillac curve for "acceptable oil consumption", and you're not alone in the 1,500 mile/quart range, either.

Keep your oil level at halfway up the dipstick mark - at the top is overfilled, and the engine will burn off the extra half quart quickly. A recent GM TSB on this.

cool cool
Thank you .

joe_mn
08-05-09, 10:40 PM
must be 1000 oil threads on the internet. there is no oil viscosity that will prevent engine wear at startup. 0w is slightly better than 5w at startup. 5w is slightly better than 10w and 10w is better than 20w. there is a reason 0w oil is in a green tinted bottle. to make you feel better.