I have used 0,5 & 10w30 and could not determine any difference in anything. Even MPG stayed the same. I’m in the greater Los Angeles area so the temps don’t get any lower than 45 degrees F in the dead of winter. I see triple digits all the time in the summer and a ton of stop and go traffic in this kind of heat, so I generally use 10w30, makes me feel better
5w30 vs 10w30
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At operating conditions they will both be about the same. At cold start up the 5W will provide better protection...
Originally Posted By: barkingspider
I have used 0,5 & 10w30 and could not determine any difference in anything. Even MPG stayed the same. I’m in the greater Los Angeles area so the temps don’t get any lower than 45 degrees F in the dead of winter. I see triple digits all the time in the summer and a ton of stop and go traffic in this kind of heat, so I generally use 10w30, makes me feel better
Not all 5w and 10w oils are created equal. Not even from the same manufacturer. SAE and API spec are quite broad.
I have used 0,5 & 10w30 and could not determine any difference in anything. Even MPG stayed the same. I’m in the greater Los Angeles area so the temps don’t get any lower than 45 degrees F in the dead of winter. I see triple digits all the time in the summer and a ton of stop and go traffic in this kind of heat, so I generally use 10w30, makes me feel better
Not all 5w and 10w oils are created equal. Not even from the same manufacturer. SAE and API spec are quite broad.
Most manuals say you can use 10W30 down to 0F or -20C which sounds about right to me. Well the OM that still show temp graphs with various grades.
The actual 10W cold cranking test (CCS) is performed at -25C and the low temp pumping test at -30C, so you know you are good down to these temps.
Above freezing, 32F or 0C, I would expect absolutely no difference in "start up flow" between a 10W and a 5W. This should not really be an issue until close to the cold cranking limits. But once at these temp limits, then yes obviously 5W is better even though 10W may still work.
But there is no free lunch, that extra cold flow comes at a cost, and given the same oil formulation, a 10W should use less polymer VII and therefore be more shear stable and have less Noack volatility.
Below 0F / -20 C then 5W30 for the cold flow.
Above 0F / -20 C then 10W30 for shear stability and low volatility.
The actual 10W cold cranking test (CCS) is performed at -25C and the low temp pumping test at -30C, so you know you are good down to these temps.
Above freezing, 32F or 0C, I would expect absolutely no difference in "start up flow" between a 10W and a 5W. This should not really be an issue until close to the cold cranking limits. But once at these temp limits, then yes obviously 5W is better even though 10W may still work.
But there is no free lunch, that extra cold flow comes at a cost, and given the same oil formulation, a 10W should use less polymer VII and therefore be more shear stable and have less Noack volatility.
Below 0F / -20 C then 5W30 for the cold flow.
Above 0F / -20 C then 10W30 for shear stability and low volatility.
Originally Posted By: Boss302fan
At operating conditions they will both be about the same. At cold start up the 5W will provide better protection...
It will make it easier to start but why will it provide better protection?
At operating conditions they will both be about the same. At cold start up the 5W will provide better protection...
It will make it easier to start but why will it provide better protection?
Originally Posted By: Boss302fan
At operating conditions they will both be about the same. At cold start up the 5W will provide better protection...
Depending on ambient temperatures as mentioned...
At operating conditions they will both be about the same. At cold start up the 5W will provide better protection...
Depending on ambient temperatures as mentioned...
10w30 was spec for years even in the North East. Never had any trouble or much warranty work for anything lube related that running a 5w30 would have made a difference eg small block cam failure and oil pressure gauge issues (not actual pressure).
I dropped 5w30 for 10w30 because of the lower NOACK values, it does make a difference in intake, TB deposits and varnish.
Personally I care more about protecting the engine than energy conserving.
I dropped 5w30 for 10w30 because of the lower NOACK values, it does make a difference in intake, TB deposits and varnish.
Personally I care more about protecting the engine than energy conserving.
The 10W30 has lower NOACK which is a good thing, but the lack of Dexos (Dexos1 Gen2, in particular) certification is a deal-breaker for me. Having a GDI engine with timing chain, a Dexos1 Gen2 5W30 oil is my choice.
In So Cal you could use Dexos 2 which is better for piston cleanliness and in general a superior oil to the Dex 1. Its OE spec for all GM gas engines in Europe.
Originally Posted By: Spitter
If temps are above freezing could 10w30 offer more cold start protection than 5w30 in a vehicle that calls for 5w30? What temps would make 5w the better choice?
In Kentucy 5W-30 and 10W-30 should make no difference in cold-start protection.
10W-30 has a thicker base oil, which may have less wear in your valvetrain and timing chain, depending on the type of your engine.
If temps are above freezing could 10w30 offer more cold start protection than 5w30 in a vehicle that calls for 5w30? What temps would make 5w the better choice?
In Kentucy 5W-30 and 10W-30 should make no difference in cold-start protection.
10W-30 has a thicker base oil, which may have less wear in your valvetrain and timing chain, depending on the type of your engine.
Id run 10w30 where I live then in Winter or late fall switch to a 0w or 5w, easy enough
Originally Posted By: Trav
In So Cal you could use Dexos 2 which is better for piston cleanliness and in general a superior oil to the Dex 1. Its OE spec for all GM gas engines in Europe.
I'm not sure that a low SAPS/TBN oil is a good call for a U.S. GDI engine with our high sulphur gas and extended OCIs.
In So Cal you could use Dexos 2 which is better for piston cleanliness and in general a superior oil to the Dex 1. Its OE spec for all GM gas engines in Europe.
I'm not sure that a low SAPS/TBN oil is a good call for a U.S. GDI engine with our high sulphur gas and extended OCIs.
10w-30 oils use much less viscosity index improver so it is a better oil for that reason alone.
The flow time of 10w-30 vs 5w-30 in the summer virtually the same.
What most fail to understand is that the wider the range, the more VI improvers are used and VI improvers
provide no lubrication and break down over time.
The flow time of 10w-30 vs 5w-30 in the summer virtually the same.
What most fail to understand is that the wider the range, the more VI improvers are used and VI improvers
provide no lubrication and break down over time.
Spitter, I see you use 5w30 for one vehicle and 10w30 for the other. You can simplify things by just using the 5w30. In a fix you can always find a 5w30 a lot easier and there's not much separating the two. For your applications the 5w is plenty good enough.
A SN+ D1 Gen 2 5W30 would be fine year round once they are widely available ... In the mean time a 10W30 synthetic has an equal flow time line until you get down to 26 degrees (based on tests I've seen where the 5W intersects the 10W flow time line at aprox 26 degrees . Here in North GA. I switch to 5W30 synthetic in the Fall as during the Winter we get temps down in the teens thus the move to 5W then .
Originally Posted By: turnbowm
Originally Posted By: Trav
In So Cal you could use Dexos 2 which is better for piston cleanliness and in general a superior oil to the Dex 1. Its OE spec for all GM gas engines in Europe.
I'm not sure that a low SAPS/TBN oil is a good call for a U.S. GDI engine with our high sulphur gas and extended OCIs.
dexos 2 will have similar, or likely higher TBN than dexos 1. I hear they have lowered the S level in US fuel anyhow.
GM Holden have revised all gasoline models in Australia where dexos 1 or dexos 2 was recommended to dexos 1 gen 2. They allow dexos 2 to be used in non turbo engines only. I expect this is the same in Europe.
Originally Posted By: Trav
In So Cal you could use Dexos 2 which is better for piston cleanliness and in general a superior oil to the Dex 1. Its OE spec for all GM gas engines in Europe.
I'm not sure that a low SAPS/TBN oil is a good call for a U.S. GDI engine with our high sulphur gas and extended OCIs.
dexos 2 will have similar, or likely higher TBN than dexos 1. I hear they have lowered the S level in US fuel anyhow.
GM Holden have revised all gasoline models in Australia where dexos 1 or dexos 2 was recommended to dexos 1 gen 2. They allow dexos 2 to be used in non turbo engines only. I expect this is the same in Europe.
A dexos2 oil may have a lower TBN than a dexos1 oil. There certainly will be examples of that case when you're looking at the top end synthetics with dexos1. Some years back, there were some rather low TBN ILSAC oils at the SM/GF-4 rollout, but that's been pretty much rectified across the baord.
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