Originally Posted By: Gokhan
Originally Posted By: JSRT4
My car always consumes some oil, which is typical for the motor I have. I'm looking to run a 40 weight oil and my preferences are Redline 5w40 , Redline 0w40, or Amsoil 0w40. The 0w40's sound tempting to get quicker flow at start-up and still a decent high temp viscosity, but the NOACK numbers increase as well. I'm wondering if oil consumption changes very much based on NOACK numbers for oils such as these ?.
Redline 5w40 is 6%, going to Redline 0w40 bumps it up to 9%. Amsoil is at 8.1%. If consumption is not drastically related to a 2-3% increase in NOACK then I'd like to run the 0w40's, if consumption does increase then the 5w40 is still a good consideration. My car is used 3 seasons only, it gets put away for winter, but early spring and late fall can see some cooler temps.
Thanks for reading and any replies.
Thanks for any opinions on this.
If you can keep the NOACK under 9 or 10% or so, evaporative contribution to the oil consumption will be negligible or small under virtually all conditions. Therefore, if your NOACK is lower than 9 or 10%, you have nothing to worry about.
Here is a paper that you can study (PDF link).
If NOACKs are below 9 or 10%, I would base the selection on viscosimetric qualities such as HTHSV, VI, KV100, KV40, and general oil quality, including the VII quality. Some 0Ws are good but some of them are not. For example, I would prefer Mobil 1 5w30 or Mobil 1 Extended Performance 5w30 over Mobil 1 Advanced Fuel Economy 0w30 because of worse viscosimetric properties of Mobil 1 0w30 than Mobil 1 5w30. However, Mobil 1 0W-40 is an excellent oil (9% or less NOACK with great additive package), beating Mobil 1 Turbo Diesel Truck 5W-40. So, there is no general rule on whether 0W- or 5W- is better.
xW-40 will definitely reduce the oil consumption over xW-30 a lot because you won't get as much oil transported through the valve guides and piston rings.
Good info GokHan,
It's one of the reasons I look for Euro ACEA A3/B oils, not just API SN oils.
Not only do the A3/B4 oils require a lower Noack than SN oils, they are also required to have a minimum TBN of 10, and pass a shear, stay-in-grade, viscosity test that means high quality VII are used. SN oils don't have to pass a shear test or have such a high TBN. Of course the A3/B4 oils are also SN rated, so warranty requirement are still OK. The A3/B4 oils that are also MB 229.5 (like the 0W40 you mentioned), steps up the quality even higher.
Just saying I agree with you completely about it's the overall package that counts, and the xW-y oil weight can only tell you so much. But the manufacturer specs that are on the oil bottle can help the consumer a lot when faced with a wall of oil at their local store.
Originally Posted By: JSRT4
My car always consumes some oil, which is typical for the motor I have. I'm looking to run a 40 weight oil and my preferences are Redline 5w40 , Redline 0w40, or Amsoil 0w40. The 0w40's sound tempting to get quicker flow at start-up and still a decent high temp viscosity, but the NOACK numbers increase as well. I'm wondering if oil consumption changes very much based on NOACK numbers for oils such as these ?.
Redline 5w40 is 6%, going to Redline 0w40 bumps it up to 9%. Amsoil is at 8.1%. If consumption is not drastically related to a 2-3% increase in NOACK then I'd like to run the 0w40's, if consumption does increase then the 5w40 is still a good consideration. My car is used 3 seasons only, it gets put away for winter, but early spring and late fall can see some cooler temps.
Thanks for reading and any replies.
Thanks for any opinions on this.
If you can keep the NOACK under 9 or 10% or so, evaporative contribution to the oil consumption will be negligible or small under virtually all conditions. Therefore, if your NOACK is lower than 9 or 10%, you have nothing to worry about.
Here is a paper that you can study (PDF link).
If NOACKs are below 9 or 10%, I would base the selection on viscosimetric qualities such as HTHSV, VI, KV100, KV40, and general oil quality, including the VII quality. Some 0Ws are good but some of them are not. For example, I would prefer Mobil 1 5w30 or Mobil 1 Extended Performance 5w30 over Mobil 1 Advanced Fuel Economy 0w30 because of worse viscosimetric properties of Mobil 1 0w30 than Mobil 1 5w30. However, Mobil 1 0W-40 is an excellent oil (9% or less NOACK with great additive package), beating Mobil 1 Turbo Diesel Truck 5W-40. So, there is no general rule on whether 0W- or 5W- is better.
xW-40 will definitely reduce the oil consumption over xW-30 a lot because you won't get as much oil transported through the valve guides and piston rings.
Good info GokHan,
It's one of the reasons I look for Euro ACEA A3/B oils, not just API SN oils.
Not only do the A3/B4 oils require a lower Noack than SN oils, they are also required to have a minimum TBN of 10, and pass a shear, stay-in-grade, viscosity test that means high quality VII are used. SN oils don't have to pass a shear test or have such a high TBN. Of course the A3/B4 oils are also SN rated, so warranty requirement are still OK. The A3/B4 oils that are also MB 229.5 (like the 0W40 you mentioned), steps up the quality even higher.
Just saying I agree with you completely about it's the overall package that counts, and the xW-y oil weight can only tell you so much. But the manufacturer specs that are on the oil bottle can help the consumer a lot when faced with a wall of oil at their local store.
