VZ LS1 engine oil

[smoken2]

Hi,

I'm wondering why there is a variation in the engine oil that is specified between the CV8Z Monaro (5W-30) and a VZ LS1 (10W-30).
I understand oil vicosity, even the GF 3 part of the engine oil specification, just don't understand why the Monaro has the lighter weight oil for start-up.
If Holden are happy with the 5W-30 than I'll use it for my next oil change, 10,000km.

[smoken2]

Hi,

Just a quick add to my original question, the price of the 5W-30 is approx. 30% above the price of the genuine 10W-30 oil at the spare parts counter.
Maybe, the lack of response from the Holden guys could signfy that the 5W-30 is a more suitable oil for the LS1, but it has a price premium over the 10W-30.
What I'm trying to say is that the 5W-30 may be a better overall oil for the
LS1, but Holden believe the 5W-30 price premium is not warranted for an LS1 not fitted to a Monaro etc.??
Any advice would be greatly appreciated.
Cheers.

[smoken2]

Yes, this must be a very technical question for Holden to answer, why did they they do......what? and the answer is.....? nobody at Holden seems to know or cares enough to give a reason why. I have asked a Holden Service Manager, no joy.

Why are two LS1's manufactured at the same time (CV8Z/ SSZ) and specified to use two different engine oils, how about some feedback, forget it I'm too old and grumpy now.

If Holden knows the reason why there is a viscosity variation, then please, pass it on to the WA Service Managers so they at least know.

[spanks]

After seeing how the standard oil pressure in a LS1 is,i would go for a thicker oil..i am running 25W50 in mine..ok so mine is not standard but i also run the same oil in the other LS1 engined cars that i work on..hope that will add some light for you..

[smoken2]

After seeing how the standard oil pressure in a LS1 is,i would go for a thicker oil..i am running 25W50 in mine..ok so mine is not standard but i also run the same oil in the other LS1 engined cars that i work on..hope that will add some light for you..
Hi Spanks,

Thanks for the feedback.

[6.0]

Ford have done a bit of a switch between oils as well.
5W-30 is recommended for the AU series 1, then 10W-30 from AU series 2, including the BA, now for the BF they recommend 5W-30 again, for fuel economy. Sounds like 5W-30 gets greater fuel economy.
This is for the base models, I beleive some HiPo models use different oil grades.
A Ford dealer bulliten in the US recommends 5W-30 for all cars, regardless of age, again for fuel economy.
I find I can usually get 5W-30 Pennzoil Semi-synthetic for a good price.