Thoughts On Synthetic 20wt. In Extreme Heat>?

[ULVER]

Everyone is trying to save every ounce of fuel these days, so I am thinking of going to Mobil 1 0-20, in all seasons. South Ga., in August is nothing but asphalt, rattlesnakes, and extreme heat.

Have the 20wt. synthetics proved themselves, under such levels of abusive temperature

Thanks for thoughts

 

[drivewaytech]

Not a concrete statement for you but I and several people I know have been running 5W-20 in metro Atlanta for years with no oil related ill-effects. I can only offer experience.

 

[MGregoir]

What is the vehicle?

 

[dnewton3]

Doesn't really matter how hot it gets outside (ambient). What matters is how well your cooling system operates.

Ambient temps don't effect to total load near as much as they effect the rate of energy transer. As long as your cooling system is sized properly, you should be able to overcome any heat load generated. Think about it this way:
1) it's ugly cold outside (-20); it takes longer to warm up, but it does eventually get warmed up to operating temps.
2) it's ugly hot outside (+110); it warms up darn quick, but it doesn't get any hotter (final temp) than if it were +75 outside.

Assuming it's running fine, then it's probably thermostatically controlled somewhere between 190-210 deg F all the time. So to that point, the xW-20 grade oil will work the same, regardless of what the outside temp is. In fact, even dino would be fine at those temps.

Now if you have a cooling system issue, such as restricted fluid flow, clogged heat exchanger (radiator), etc., then the coolant will get too hot and that will make the oil hot. But that's not the oil's fault now, is it?

 

[JAG]

A cooling system in which the thermostat is fully open will cause the coolant to get hotter as ambient temps rise. Other than radiator fans running full-time, it has done all the correction it can to control the coolant temp.

This is a diesel engine forum. Is the engine really a diesel? A 20 weight oil in a diesel is a rare practice.

 

[salesrep]

You'll be fine running 20 wt.

 

[bmwtechguy]

If it is designed to run on SAE 20 grade oil, it should be fine. As JAG pointed out, most diesel engines are not designed for it.

 

[ULVER]

Sorry guys... This is what I get for leaving the reading glasses in the bedroom. Posted in the wrong section. I can't blame this one on the wife.

FYI-The vehicle is a 2006 Ford Crown Vic Police Interceptor. V8 GAS engine. I bought it from the dept., after they took it out of service.

Even though Ford states that 5-20 is the desired oil for the vehicle, a lot of agencies I have talked to, continue to use 5-30; the weight the engine was designed around well-over 15 years ago. It's only 281ci., and revs very high, and some say the 20wt., is all about MPG, not engine life.

I will still like to hear what you folks think about the original question. Do you feel comfortable with a 20wt. synthetic under extreme heat?

Again, sorry for invading your forum!

Thanks for any thoughts.

 

[SonyAD]

I'm by no means an expert but I wouldn't use a w30 weight oil in my car. Let alone a w20. Let alone in a gasser, which runs hotter.

Why doesn't Ford recommend a 0w20? Why a 5w20?

 

[artificialist]

I'm running Quaker State synthetic in my mom's Jeep 3.7 and everything is fine.

 

[BuickGN]

Originally Posted By: dnewton3
Doesn't really matter how hot it gets outside (ambient). What matters is how well your cooling system operates.

Ambient temps don't effect to total load near as much as they effect the rate of energy transer. As long as your cooling system is sized properly, you should be able to overcome any heat load generated. Think about it this way:
1) it's ugly cold outside (-20); it takes longer to warm up, but it does eventually get warmed up to operating temps.
2) it's ugly hot outside (+110); it warms up darn quick, but it doesn't get any hotter (final temp) than if it were +75 outside.

Assuming it's running fine, then it's probably thermostatically controlled somewhere between 190-210 deg F all the time. So to that point, the xW-20 grade oil will work the same, regardless of what the outside temp is. In fact, even dino would be fine at those temps.

Now if you have a cooling system issue, such as restricted fluid flow, clogged heat exchanger (radiator), etc., then the coolant will get too hot and that will make the oil hot. But that's not the oil's fault now, is it?


I agree somewhat but with an oil temp guage in the GN and a very good cooling system, my oil temp rises in the summer by nearly half of the ambient change. Water temp runs dead on 170 degrees summer or winter.

Since I see hot summers, long trips, and my engine originally called for a 10-30, I use a 10-30. If I ever decided to track it, it would get a 15-40.

 

[Steve S]

There always be a temperature differential due to the ambient temps . With out a big load and hot temps the difference may never be noticed . Years ago I used to drive trucks to make extra $$$ I have made many trips from San Francisco to Los Angeles and I can tell you that at max load when leaving Los Angles going over the grapevine all the temps of everything that has gauges read really hot when there is a hot spell as compared to when it is cooler. In most unloaded conditions "passenger" cars you may never see the difference. What is extreme heat in Georgia .I have been there to the carpet mill towns and Atlanta ,it was in the 1970s I really don't remember anything but humidity. Does your oil get hot enough to warrant synthetics?

 

[BuickGN]

Originally Posted By: Steve S
There always be a temperature differential due to the ambient temps . With out a big load and hot temps the difference may never be noticed . Years ago I used to drive trucks to make extra $$$ I have made many trips from San Francisco to Los Angeles and I can tell you that at max load when leaving Los Angles going over the grapevine all the temps of everything that has gauges read really hot when there is a hot spell as compared to when it is cooler. In most unloaded conditions "passenger" cars you may never see the difference. What is extreme heat in Georgia .I have been there to the carpet mill towns and Atlanta ,it was in the 1970s I really don't remember anything but humidity. Does your oil get hot enough to warrant synthetics?


Sort of off topic but I took the TL over the grapevine for the 4th of July weekend with 4 people and their luggage with 100lbs in subs and we were late so instead of my usual 65mph I was going 80mph and ambient was 95 degrees. It did enter my mind that I was happy to have a good 30wt synthetic in there.

 

[ULVER]

Originally Posted By: Steve S
There always be a temperature differential due to the ambient temps . With out a big load and hot temps the difference may never be noticed . Years ago I used to drive trucks to make extra $$$ I have made many trips from San Francisco to Los Angeles and I can tell you that at max load when leaving Los Angles going over the grapevine all the temps of everything that has gauges read really hot when there is a hot spell as compared to when it is cooler. In most unloaded conditions "passenger" cars you may never see the difference. What is extreme heat in Georgia .I have been there to the carpet mill towns and Atlanta ,it was in the 1970s I really don't remember anything but humidity. Does your oil get hot enough to warrant synthetics?


It can get pretty brutal... But I am a synthetic kinda guy since the early 80's. Never going back!

 

[SonyAD]

Ambient temperatures and load affect both water and oil temperatures profoundly even with a well functioning cooling system.

That 20wt will turn to water when you most need it...

 

[simple_gifts]

Quote:

That 20wt will turn to water when you most need it...

Evidence points to the contrary.

 

[crazyoildude]

5w20 seems to perform well, years ago i believed thicker was better now i am a believer in 5w20 the faster the oil circulates the faster the oil gets to the bearings and all vital parts including valve guides which is important for valve guide wear reasons. Also tighter bearing clearances require lighter oil to prevent starvation of oil at the bearings

 

[SonyAD]

284 fahrenheit is normal operating temperature in my turbodiesel. Would a 0w20 or 0w30 hold up to that?

Would the oil film of a 20wt on the main bearings, crank journals, wrist pins and cylinder walls prevent contact when the engine is putting out 151 lb/ft at 1750 rpm?

 

[simple_gifts]

Quote:

Would a 0w20 or 0w30 hold up to that?

No one is talking about using it in an app not specified to use it.

Perhaps you missed

Quote:

Posted in the wrong section.

...The vehicle is a 2006 Ford Crown Vic Police Interceptor. V8 GAS engine

 

[BuickGN]

Originally Posted By: crazyoildude
5w20 seems to perform well, years ago i believed thicker was better now i am a believer in 5w20 the faster the oil circulates the faster the oil gets to the bearings and all vital parts including valve guides which is important for valve guide wear reasons. Also tighter bearing clearances require lighter oil to prevent starvation of oil at the bearings


It goes back to the old do you want a thicker film sitting on parts before the pressure gets there or do you want a thinner film on parts with oil pressure the gets there .000001 second quicker. Valve guides aren't supposed to see any oil, not much anyway, that's why they have valve stem seals, to keep oil away or to control how much oil gets down there.