Going up an extrememly steep hill on way to my sons state track meet. We are crawling and sometimes at a standstill on this long hill. Not using my AC at the time. But the temp gauge was up 3/4, almost to the top while stopped and idling and crawling up this hill and it was pretty warm out.. The gauge never went any further but it stayed there until we crested the hill. I use conventional 5/30. Would a thicker oil like a 10/30 in hot weather keep the engine cooler? Or was this norma and worrying about nothing?
Question About Thinner OIls in Hot Weahter
- Thread starter Mark72
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10W-30 isn't thicker than 5w30; they are both 30 weight oils.
Your primary situation is a cooling system issue, not an oil weight issue IMHO. Make sure your radiator is not dirt covered or plugged is a good 1st step.
Your primary situation is a cooling system issue, not an oil weight issue IMHO. Make sure your radiator is not dirt covered or plugged is a good 1st step.
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The opposite is true for my E430. When it had M1 0W40 the coolant temp was 210-220F when we passed Death Valley climbing up steep hills in summer, it was only 195-200F with xW20 when ambient temp was 120+.
If the motor is overheating, focus your efforts on the cooling system. At temperature, Xw30s are all basically the same.
A 10W-30 is generally somewhat thicker than a 5w30 of the same oil brand for three reasons;
It usually has a higher HTHS vis and it always has a lower VI which primarily means a higher viscosity at low oils temp's but also at high oil temp's but to a lesser extent. It also may be less prone to oil shear.
Higher coolant temp's will mean higher oil temp's but not too high oil temp's necessitating increasing the oil viscosity.
It's only if you are using full throttle and maximum rev's for an extended period of time that one would need to be possibly concerned about oil temp's. And from the sounds of things that's not what you're doing.
It usually has a higher HTHS vis and it always has a lower VI which primarily means a higher viscosity at low oils temp's but also at high oil temp's but to a lesser extent. It also may be less prone to oil shear.
Higher coolant temp's will mean higher oil temp's but not too high oil temp's necessitating increasing the oil viscosity.
It's only if you are using full throttle and maximum rev's for an extended period of time that one would need to be possibly concerned about oil temp's. And from the sounds of things that's not what you're doing.
Thinner oil will dissipate/shed heat more quickly than a thicker oil with all conditions being equal.
Probably just chalk it up to a coolant system thats either a bit cruded up or more likely, under-engineered from the start.With the higher heat load and no/little airflow across the rad =higher temps.Years ago we would scour junkyards for the big 4 and 5 core rads from trucks for extra cooling,and have them hot dipped, rodded out and brazed up at a shop, now of course there's the internet.Unfortunately the all aluminum rads are very expensive,but aux trany and engine oil coolers are priced ok.
i think its normal. your were putting the vehicle under a heavy load and it warmed up. 3/4 is not too bad, it just means the engine is under stress.
a 10/30 is not that much thicker but it will take more heat than a 5w30 because it has less additives to drop the cold cranking visc.
running a 10/30 would not be a bad idea in summer, but you probably dont need it unless your going to strain the engine alot.
its my opinion that this is one of those times a syn will out perform dino, so you might think about switching.
if your going to work the engine hard like this alot you might look into aux coolers. jegs has a combo oil/atf cooler with thermostat activated fan. it might be a good idea because if your water temp is up your oil and atf might be too. cooling all the fluids will help the engine run cooler as a whole.
a 10/30 is not that much thicker but it will take more heat than a 5w30 because it has less additives to drop the cold cranking visc.
running a 10/30 would not be a bad idea in summer, but you probably dont need it unless your going to strain the engine alot.
its my opinion that this is one of those times a syn will out perform dino, so you might think about switching.
if your going to work the engine hard like this alot you might look into aux coolers. jegs has a combo oil/atf cooler with thermostat activated fan. it might be a good idea because if your water temp is up your oil and atf might be too. cooling all the fluids will help the engine run cooler as a whole.
A thicker oil would not keep it cooler.
A thinner oil might.
[I am talking about oil temps]
Your problem is a cooling system one. Maybe the fan switch goes on too late? Bad belt or impeller? clogged radiator outside or inside? Overheating trans which heated up the radiator fluid?
A thinner oil might.
[I am talking about oil temps]
Your problem is a cooling system one. Maybe the fan switch goes on too late? Bad belt or impeller? clogged radiator outside or inside? Overheating trans which heated up the radiator fluid?
they have steep hills in Illinois?
One side note, you'd be surprised how much dust and grit you can blow out of your radiator using an air compressor with a flexible attachment. Forcing air from the motor side of the radiator out the grille side will clear the fins out and help it better disapate heat.
Originally Posted By: Mark72
Going up an extrememly steep hill on way to my sons state track meet. We are crawling and sometimes at a standstill on this long hill. Not using my AC at the time. But the temp gauge was up 3/4, almost to the top while stopped and idling and crawling up this hill and it was pretty warm out.. The gauge never went any further but it stayed there until we crested the hill. I use conventional 5/30. Would a thicker oil like a 10/30 in hot weather keep the engine cooler? Or was this norma and worrying about nothing?
As everyone has said, it's a cooling issue. With that being said my temp gauge is ever so slightly lower with a 5w30 as opposed to 10w30. It's been said many times before that the gauges aren't sensitive and the range for the pointer being in the "normal spot" is rather large so how much that little bit means is anyone's guess. I don't have an oil temperature gauge so nothing accurate to go on.
To answer your question though, no a thicker oil would not keep the engine cooler. A thinner oil might.
If the cooling system is fine then the next big factor is an underpowered engine and too high of a gear. High gear + low power = torque convertor uncouples and generates tons of heat which is transferred to the radiator via the transmission cooling lines. Try putting it in a lower gear next time and see how it does.
Going up an extrememly steep hill on way to my sons state track meet. We are crawling and sometimes at a standstill on this long hill. Not using my AC at the time. But the temp gauge was up 3/4, almost to the top while stopped and idling and crawling up this hill and it was pretty warm out.. The gauge never went any further but it stayed there until we crested the hill. I use conventional 5/30. Would a thicker oil like a 10/30 in hot weather keep the engine cooler? Or was this norma and worrying about nothing?
As everyone has said, it's a cooling issue. With that being said my temp gauge is ever so slightly lower with a 5w30 as opposed to 10w30. It's been said many times before that the gauges aren't sensitive and the range for the pointer being in the "normal spot" is rather large so how much that little bit means is anyone's guess. I don't have an oil temperature gauge so nothing accurate to go on.
To answer your question though, no a thicker oil would not keep the engine cooler. A thinner oil might.
If the cooling system is fine then the next big factor is an underpowered engine and too high of a gear. High gear + low power = torque convertor uncouples and generates tons of heat which is transferred to the radiator via the transmission cooling lines. Try putting it in a lower gear next time and see how it does.
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