Do not use a 160 stat!!!
Winter oil ??
Thread Starter
Burning Brakes
Joined: Mar 2013
Posts: 754
Likes: 79
From: Jacobstown, New Jersey
Winter oil ??
I have a 13' Grand Sport with a dry sump. I know it calls for 5w30 but my question is can I go to 0w30 for the winter. In cold weather my oil temperature only reaches about 135 degrees with that big oil cooler out front. I don't mind changing oil again in the spring even though there won't be many miles on the oil. I don't want to damage the motor if that's what 0w30 will do but I'm thinking with the oil temp only reaching 130-135 during the cold wether, that's can't be good for it either. Need some help by somebody more oil savy that I am. Thanks
Melting Slicks
Joined: Aug 2000
Posts: 2,327
Likes: 44
From: Sacramento CA
I had an 07 Z with that big cooler and did the same thing. Eventually sold the car and got a 13 GS wet sump.
Now that I sold the Z, I've found that some have blocked off the cooler in cold weather. They make a wrap that goes around the cooler. It is more important to get the oil up to proper operating temp. than reducing viscosity.
Hope one of the guys that has done that will help..
Now that I sold the Z, I've found that some have blocked off the cooler in cold weather. They make a wrap that goes around the cooler. It is more important to get the oil up to proper operating temp. than reducing viscosity.
Hope one of the guys that has done that will help..
Race Director
Joined: Sep 2007
Posts: 16,557
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From: Peoria/Phoenix AZ
C6 of Year Finalist (performance mods) 2019
0W30 won't hurt the engine. I run it all year in the Phoenix area, even when the outside temps get into the 110+ range.
What you need, along with all the others with dry sump systems, is an oil temp t-stat. Then the oil will bypass the cooler until it reaches the specific temperature of the t-stat. T-stats are available in 180, and 200 degree ranges.
What you need, along with all the others with dry sump systems, is an oil temp t-stat. Then the oil will bypass the cooler until it reaches the specific temperature of the t-stat. T-stats are available in 180, and 200 degree ranges.
Last edited by HOXXOH; Oct 28, 2015 at 11:27 AM.
Race Director
Joined: Aug 2005
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From: Hudson WI
NCM Sinkhole Donor
210 degrees is perfect. The additive packages in the oil don't work until 180. I made a carbon fiber grill filler to get my temps up on cold days. Before I retired and went to work for an oil company, I always thought cooler was better, found out cold oil is hard on the engine.
Race Director
Joined: Sep 2007
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From: Peoria/Phoenix AZ
C6 of Year Finalist (performance mods) 2019
Le Mans Master
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Burning Brakes
Joined: Aug 2014
Posts: 1,240
Likes: 258
From: Tampa FL
I have a 13' Grand Sport with a dry sump. I know it calls for 5w30 but my question is can I go to 0w30 for the winter. In cold weather my oil temperature only reaches about 135 degrees with that big oil cooler out front. I don't mind changing oil again in the spring even though there won't be many miles on the oil. I don't want to damage the motor if that's what 0w30 will do but I'm thinking with the oil temp only reaching 130-135 during the cold wether, that's can't be good for it either. Need some help by somebody more oil savy that I am. Thanks
My understanding oil viscosity of 5W30 means. No thiner than 5 in heat no thicker than 30 in cold.
Team Owner
Joined: Mar 2008
Posts: 21,502
Likes: 465
From: Southern Utah
A piece of aluminum foil over part of the oil cooler will allow oil temps to rise. You can try covering half the cooler, then check temps after driving, then vary the coverage accordingly. You can just crimp the foil over the cooler by hand...no big deal. As far as thinner oil, remember that it is only the temp of the car and oil when you start the car that is important. Once the car is being driven, the oil temp will come up and be fairly stable. So if the car sits outside and is started when it is very cold out, then thinner oil is of benefit because it stays thinner and circulates fater in those few minutes before the car warms up. If, however, the car is in a garage at 50 degrees when it is started, there is no benefit going lower than the 5w-30 that is normal temp oil.
To clarify, the running oil temp should be corrected by lowering the effect of the oil cooler. Trying to compensate for that low temp by using a different oil is the wrong approach.
To clarify, the running oil temp should be corrected by lowering the effect of the oil cooler. Trying to compensate for that low temp by using a different oil is the wrong approach.
Last edited by cclive; Oct 28, 2015 at 02:10 PM.
Thread Starter
Burning Brakes
Joined: Mar 2013
Posts: 754
Likes: 79
From: Jacobstown, New Jersey
Ok, I really appreciate all the help, but it still leaves me a little confused by some of the statements on here. First of all I have tried coverning the oil cooler and that didn't make a whole lot of difference. I don't know who to agree with here as far as what the numbers (5-30 really stand for. I always thought it ment when cold the oil flows a 5 and when cold it flows as 30. If anyone has ever poured oil out of a jug in winter you know it is very think and when draining it from a hot engine it is very thin so this theory never made sense to me. The other statement makes sense and this is the first time I've heard it, cold it flows no thiner than 5 and hot no thicker than 30 weight. The oil T-stat sounds like the best way to go, has anyone installed one of these and has it worked for you and where did you get it. Thanks for all the input guys.
Last edited by tealex; Oct 28, 2015 at 02:28 PM.
Team Owner
Joined: Mar 2008
Posts: 21,502
Likes: 465
From: Southern Utah
Ok, I really appreciate all the help, but it still leaves me a little confused by some of the statements on here. First of all I have tried coverning the oil cooler and that didn't make a whole lot of difference. I don't know who to agree with here as far as what the numbers (5-30 really stand for. I always thought it ment when cold the oil flows a 5 and when cold it flows as 30. If anyone has ever poured oil out of a jug in winter you know it is very think and when draining it from a hot engine it is very thin so this theory never made sense to me. The other statement makes sense and this is the first time I've heard it, cold it flows no thiner than 5 and hot no thicker than 30 weight. The oil T-stat sounds like the best way to go, has anyone installed one of these and has it worked for you and where did you get it. Thanks for all the input guys.
The Society of Automotive Engineers (SAE) has established a numerical code system for grading motor oils according to their viscosity characteristics. SAE viscosity gradings include the following, from low to high viscosity: 0, 5, 10, 15, 20, 25, 30, 40, 50 or 60. The numbers 0, 5, 10, 15 and 25 are suffixed with the letter W, designating they are "winter" (not "weight") or cold-start viscosity, at lower temperature. The number 20 comes with or without a W, depending on whether it is being used to denote a cold or hot viscosity grade. The document SAE J300 defines the viscometrics related to these grades.
Covering the oil cooler should make a significant difference. Are you sure you are covering the right cooler?
Thread Starter
Burning Brakes
Joined: Mar 2013
Posts: 754
Likes: 79
From: Jacobstown, New Jersey
0W30 won't hurt the engine. I run it all year in the Phoenix area, even when the outside temps get into the 110+ range.
What you need, along with all the others with dry sump systems, is an oil temp t-stat. Then the oil will bypass the cooler until it reaches the specific temperature of the t-stat. T-stats are available in 180, and 200 degree ranges.
What you need, along with all the others with dry sump systems, is an oil temp t-stat. Then the oil will bypass the cooler until it reaches the specific temperature of the t-stat. T-stats are available in 180, and 200 degree ranges.
Team Owner
Joined: Mar 2008
Posts: 21,502
Likes: 465
From: Southern Utah
Thread Starter
Burning Brakes
Joined: Mar 2013
Posts: 754
Likes: 79
From: Jacobstown, New Jersey
It helps a lot to have some hard data to understand viscosity grades so for reference, the SAE J300 engine oil viscosity chart is given below:
As you can see, there are three tests performed that define the viscosity grade for "W" or winter ratings. The first is "Low Temperature Cranking Viscosity" given in cP or centi-Poise to give an indication of the oil to flow sufficiently when cranking the engine...the rating temperature is lowered 5°C for each 5W drop in viscosity grade. The second is "Low Temperature Pumping" or the temperature at which the oil can be pumped which is given as 60,000 cP...the lower the viscosity grade, the lower the temperature at which the oil is capable of being pumped. The third is "Minimum Kinematic Viscosity" given is cSt or centi-Stokes and measured at 100°C/212°F...there is no maximum kinematic viscosity. The winter viscosity grades starts at "0W" and continues to "25W" in increments of 5.
For the non-winter viscosity grades, there are three ratings for those too. There are the "Minimum Kinematic Viscosity" and "Maximum Kinematic Viscosity" ratings given in cSt and measured at 100°C/212°F. You choose the viscosity grade based on the operating temperature of the oil you're experiencing to maintain 9-12 cSt for optimum lubrication. The disclaimer as noted above is you want the minimum oil temperature to be at least 180°F and preferably 200°F to ensure quicker evaporation of moisture that condensed in the engine and as well as H2O in the piston ring blow-by gas (H2O is a by-product of combustion). Also, the temperature at which the ZDDP anti-wear additive starts working is around 200°F...I can't remember the exact temperature. The third rating is the "High Temperature/High Shear" rating measured in cP at 150°C/302°F to indicate the ability of the oil to provide lubrication in extreme conditions and resist shearing down to a lower viscosity. The viscosity grades are 8, 12, 16, 20, 30, 40, 50, and 60. (There is no 0, 5, 10, or 15 as noted in the post above quoted from Wiki.)
The SAE J300 chart was updated in Jan 2015 to reflect the new grades of 8, 12, and 16...yes, soon you'll be seeing 0W8 oil. These numbers are not in increments of 5 and were intentionally chosen so as not to be confused with the winter ratings. It should be noted the viscosity ratings are "arbitrarily" chosen meaning they have absolutely no correlation to each other...a 20 weight oil is not twice as thin as a 40 weight oil or it's viscosity is not half as much. To show how arbitrary viscosity grades are, look at the chart below of SAE J306 which is the viscosity ratings for gear oils:
You can see for a 75W90 gear oil, the 75W viscosity grade has the same low temperature kinematic viscosity of a 10W viscosity grade engine oil and the 90 viscosity grade has a kinematic viscosity range at 100°C/212°F between the kinematic viscosity range of a 30 viscosity grade and a 40 viscosity grade. A 75W90 viscosity grade gear oil has the same absolute kinematic viscosity of a 10W30/10W40 viscosity grade engine oil. Why did they do that? The additive package for gear oil is completely different from the additive package for engine oil, the different "numbers" prevents the unknowing consumer from picking up any bottle of 10W30 oil if the numbers were the same and putting gear oil in the engine or vice versa...engines and differentials would be failing left and right. The funny thing is people have the perception that gear oil is much thicker than engine oil because 75W90 is a higher number than 10W30 while the reality is they are the same absolute viscosity. However, the average consumer would never dream of putting that "thick" gear oil in their engine...the SAE has achieved their goal.
As noted above, running a 0W30 in the summer when temperatures won't go below 50°F won't help much. However, it won't hurt anything either as the 0W rating is just an indication of how well the oil flows when cold. The 0W rated oil will flow slightly better at 50°F than a 5W rated oil but not by much, the lack of a huge difference isn't cause to change to a different viscosity oil though...HOXXOH stated above he uses 0W30 year round in Phoenix, AZ and I used it year round when I lived in Florida.
As you can see, there are three tests performed that define the viscosity grade for "W" or winter ratings. The first is "Low Temperature Cranking Viscosity" given in cP or centi-Poise to give an indication of the oil to flow sufficiently when cranking the engine...the rating temperature is lowered 5°C for each 5W drop in viscosity grade. The second is "Low Temperature Pumping" or the temperature at which the oil can be pumped which is given as 60,000 cP...the lower the viscosity grade, the lower the temperature at which the oil is capable of being pumped. The third is "Minimum Kinematic Viscosity" given is cSt or centi-Stokes and measured at 100°C/212°F...there is no maximum kinematic viscosity. The winter viscosity grades starts at "0W" and continues to "25W" in increments of 5.
For the non-winter viscosity grades, there are three ratings for those too. There are the "Minimum Kinematic Viscosity" and "Maximum Kinematic Viscosity" ratings given in cSt and measured at 100°C/212°F. You choose the viscosity grade based on the operating temperature of the oil you're experiencing to maintain 9-12 cSt for optimum lubrication. The disclaimer as noted above is you want the minimum oil temperature to be at least 180°F and preferably 200°F to ensure quicker evaporation of moisture that condensed in the engine and as well as H2O in the piston ring blow-by gas (H2O is a by-product of combustion). Also, the temperature at which the ZDDP anti-wear additive starts working is around 200°F...I can't remember the exact temperature. The third rating is the "High Temperature/High Shear" rating measured in cP at 150°C/302°F to indicate the ability of the oil to provide lubrication in extreme conditions and resist shearing down to a lower viscosity. The viscosity grades are 8, 12, 16, 20, 30, 40, 50, and 60. (There is no 0, 5, 10, or 15 as noted in the post above quoted from Wiki.)
The SAE J300 chart was updated in Jan 2015 to reflect the new grades of 8, 12, and 16...yes, soon you'll be seeing 0W8 oil. These numbers are not in increments of 5 and were intentionally chosen so as not to be confused with the winter ratings. It should be noted the viscosity ratings are "arbitrarily" chosen meaning they have absolutely no correlation to each other...a 20 weight oil is not twice as thin as a 40 weight oil or it's viscosity is not half as much. To show how arbitrary viscosity grades are, look at the chart below of SAE J306 which is the viscosity ratings for gear oils:
You can see for a 75W90 gear oil, the 75W viscosity grade has the same low temperature kinematic viscosity of a 10W viscosity grade engine oil and the 90 viscosity grade has a kinematic viscosity range at 100°C/212°F between the kinematic viscosity range of a 30 viscosity grade and a 40 viscosity grade. A 75W90 viscosity grade gear oil has the same absolute kinematic viscosity of a 10W30/10W40 viscosity grade engine oil. Why did they do that? The additive package for gear oil is completely different from the additive package for engine oil, the different "numbers" prevents the unknowing consumer from picking up any bottle of 10W30 oil if the numbers were the same and putting gear oil in the engine or vice versa...engines and differentials would be failing left and right. The funny thing is people have the perception that gear oil is much thicker than engine oil because 75W90 is a higher number than 10W30 while the reality is they are the same absolute viscosity. However, the average consumer would never dream of putting that "thick" gear oil in their engine...the SAE has achieved their goal.
As noted above, running a 0W30 in the summer when temperatures won't go below 50°F won't help much. However, it won't hurt anything either as the 0W rating is just an indication of how well the oil flows when cold. The 0W rated oil will flow slightly better at 50°F than a 5W rated oil but not by much, the lack of a huge difference isn't cause to change to a different viscosity oil though...HOXXOH stated above he uses 0W30 year round in Phoenix, AZ and I used it year round when I lived in Florida.
Race Director
Joined: Sep 2007
Posts: 16,557
Likes: 2,108
From: Peoria/Phoenix AZ
C6 of Year Finalist (performance mods) 2019
Second is that the only 0W30 that's commonly available is the Advanced Fuel Economy oil from Mobil 1. The downside of using that oil, is the ZDDP is also lower than the 5W30, which is also a little light on ZDDP, due to gov't restrictions. I use 1 quart of 0W30 Racing that has a much too high ZDDP and 4.5 quarts of the AFE. That give me the correct additives for economy and wear. Since drag racing doesn't create long term excessive heat, the blend works well.
Third is that I'm not forced to change oil for the racing season (Winter), since the oil will perform just as well in the heat of the Summer as the cold (alltime record low in Phoenix is 18) of the Winter. A Summertime worst case oil temperature would be about 240, compared to a Winter worse case of about 230 and both are well within the normal operating range.
Google oil t-stats. There are several brands ranging in price from about $50 to $250. I use a Derale for my transmission to assure a minimum temp for racing, but living in the desert, I have no need to quickly warm the engine oil.
Race Director
Joined: Sep 2007
Posts: 16,557
Likes: 2,108
From: Peoria/Phoenix AZ
C6 of Year Finalist (performance mods) 2019
AFAIK, no one makes a 0W30, except for racing, with a high enough ZDDP content to withstand the wear concerns of high performance engines. The 0W30 for racing is not commercially available, nor is it cheap. Yes, the 0W30 is speced for some cars, but those are all low performance cars.
Team Owner
Joined: Mar 2008
Posts: 21,502
Likes: 465
From: Southern Utah
Racing oil sounds great...sounds like your car is a racing car. The problem is that racing cars are designed to finish one race, which might be up to 500 miles or so. Our cars, even the garage queens, need to last into the hundreds of thousands of miles, and racing oil is just not designed to do this. Sludge, deposits and wear are just not concerns when your only goal with the car is to win the next race. The engine will be torn down at a minimum and likely replaced before the next race. Not so with our cars.