5W-20 in a Camry

[Daniel M. Dreifus]

Originally Posted by rimfire,22

My goal is getting the best mileage

There's a lot of focus on fuel economy these days, but actually is a small component of the overall cost of the car.
I've found it better to just keep up with traffic and not worry too much about mileage. Works out better than becoming a hindrance to other cars by accelerating gently and coasting to stops. I average around 22 mpg on the '94 4 cyl. with mostly city and some highway and I wind up the engine as needed. Your '89 should do a bit better with the smaller engine.

[arfa1980]

Synthetic oils tend to perform well at extremely low tempertures and they are stable at extremely high temperatures. they will have longer life time. The viscosity index is high which may give less viscous drag during starting and provide thicker oil film for better sealing and wear prevention. . If you are in a cold area, synthetic oil will perhaps reduce the fuel consumption. But if you don't have a frequent cold start, you only need to assure sufficient viscosity at normal operating T to provide suitable lubricating film.
SInce your engine is pretty old, the condition inside the engine could be not as good as a new one. And you already are using 5W, which can perform at
-25C. I will say the fuel type maybe have more impact on the gas mileage. it is a very complicated issue. you can try to see if it works better.
Thanks

[rimfire,22]

Originally Posted by arfa1980

Synthetic oils tend to perform well at extremely low tempertures and they are stable at extremely high temperatures. they will have longer life time. The viscosity index is high which may give less viscous drag during starting and provide thicker oil film for better sealing and wear prevention. . If you are in a cold area, synthetic oil will perhaps reduce the fuel consumption. But if you don't have a frequent cold start, you only need to assure sufficient viscosity at normal operating T to provide suitable lubricating film.
SInce your engine is pretty old, the condition inside the engine could be not as good as a new one. And you already are using 5W, which can perform at
-25C. I will say the fuel type maybe have more impact on the gas mileage. it is a very complicated issue. you can try to see if it works better.
Thanks

arfa1980,

Here in California I'll try anything minus driving to get better mileage. Currently gas is over $3 bucks and still rising.

My main reason I sue synthetic oil is to keep the oil as clean as possible before changing it during the scheduled oil change. I don't extend my driving miles but instead use the oil and change it as per the maintenance schedule. The inner workings/cleaniness is also important too me. I was told that synthetic oil keeps the inner parts cleaner compared to conventional dino oil.

Like I said before I'll have to slow down and keep the tires and filter proper. Branded gasoline is very high in price. I currently use Costco gasoline as it's usually a dime cheaper than Chevron, Conoco 76, Shell etc. These gaolines are much better BUT terribly expensive. Here in California were all in pretty bad shape. I'm even considering driving more during the nighttime just to see if the cold air might have some small impact on MPG.

rimfire,22

[CF#5]

Am I to conclude from all this discussion that thinner oil helps improve gas mileage? Or is it more a function of the synthetic oil as opposed to the viscosity?

I've been using 20W-50 conventional oil with changes every 2500-3000 miles in my high mileage gen 1 Camry to reduce leakage.

Occasionally I've used Castrol Syntec 15W-40 blend in the past and I didn't notice much of a difference in anything. The car performed normally in every observable way with that oil.

[xfeejayx]

here are my suggestions since you are really worried about overall cost of maintaining your car:
stop using synthetic oil for oil changes. My opinion on the matter is that since you are changing at the regular interval anyway, you won't see any difference with using regular oil. Synthetic is great and all, but there is absolutely nothing wrong with regular oil. The only reason I would consider using synthetic (keeping cost in mind) is if I wanted to extend oil change intervals. Aside from that, I think it to be unnecessary in most applications.

Stop using cheap gas. I think quality gas does make a difference. Fuel injectors, to me, are more important to fuel economy than the type of oil you are using. 'Bad' gas=dirty injectors. Save our money on the synthetic oil, spend it on quality gas, run a bottle of injector cleaner through it every oil change. I honestly think you'll see a difference.

Also, if you have a lot of extra weight in your car, take it out. makes a HUGE difference.

for reference, my 98 2.2L with ~145k will still get at least 25 city, average 26-27. With a gentle foot I can get 31-35 highway, average 32.

[rimfire,22]

Originally Posted by xfeejayx

here are my suggestions since you are really worried about overall cost of maintaining your car:
stop using synthetic oil for oil changes. My opinion on the matter is that since you are changing at the regular interval anyway, you won't see any difference with using regular oil. Synthetic is great and all, but there is absolutely nothing wrong with regular oil. The only reason I would consider using synthetic (keeping cost in mind) is if I wanted to extend oil change intervals. Aside from that, I think it to be unnecessary in most applications.

Stop using cheap gas. I think quality gas does make a difference. Fuel injectors, to me, are more important to fuel economy than the type of oil you are using. 'Bad' gas=dirty injectors. Save our money on the synthetic oil, spend it on quality gas, run a bottle of injector cleaner through it every oil change. I honestly think you'll see a difference.

Also, if you have a lot of extra weight in your car, take it out. makes a HUGE difference.

for reference, my 98 2.2L with ~145k will still get at least 25 city, average 26-27. With a gentle foot I can get 31-35 highway, average 32.

xfeejayx,

I use synthetic oil for longevity. My question was the weight of the newer generation oils that go light. 5W-20 is what I wonder will save me a few bucks. Perhaps yes...perhaps not. Currently I use M1 5W-30 weight. Mainly I check my tires for proper pressure and keep the air filter checked when the oils changes. As for cheap gas here in Los Angeles there is no such thing. Gas cost so much that off brand gasoline cost just a few cents lower than good branded versions. No matter what I may have to tank up with I always run a bottle of "Techron" through my cars every couple months as a precaution.

rimfire,22

[Brian R.]

Originally Posted by CF#5

Am I to conclude from all this discussion that thinner oil helps improve gas mileage? Or is it more a function of the synthetic oil as opposed to the viscosity?

Any increase in gas mileage will be due to the change in viscosity. There is also a significant difference between synthetic and dino oil in oil lubrication quality as the oil ages and degrades. The synthetic oil is still new at 3k miles after the oil change. The dino oil is more viscous at this mileage, and has lost some of its lubricating properties due to shear break-down and oxidation. The anti-oxidants protect it for the most part, but not totally. Synthetic oil is vastly superior to dino oil in resisting oxidation and shear.

[rimfire,22]

Originally Posted by Brian R.

Any increase in gas mileage will be due to the change in viscosity. There is also a significant difference between synthetic and dino oil in oil lubrication quality as the oil ages and degrades. The synthetic oil is still new at 3k miles after the oil change. The dino oil is more viscous at this mileage, and has lost some of its lubricating properties due to shear break-down and oxidation. The anti-oxidants protect it for the most part, but not totally. Synthetic oil is vastly superior to dino oil in resisting oxidation and shear.

Brian R,

Thanks for your posting. This is one of the reasons why I prefer to use a synthetic oil instead of dino.

rimfire,22

[JOET/CAMRY]

Originally Posted by rimfire,22

I'm even considering driving more during the nighttime just to see if the cold air might have some small impact on MPG.

rimfire,22

The cold air would likely have a negative impact on your MPG.
the engine would take longer to heat up to normal operating temperature in cool weather than in warm weather.
an engine running at normal operating temperature gets better MPG than a cold engine.

Regards,
JOET/CAMRY (1989 Camry owner)

[rimfire,22]

Originally Posted by JOET/CAMRY

The cold air would likely have a negative impact on your MPG.
the engine would take longer to heat up to normal operating temperature in cool weather than in warm weather.
an engine running at normal operating temperature gets better MPG than a cold engine.

Regards,
JOET/CAMRY (1989 Camry owner)

JOET/CAMRY,

You could be right. I heard that since cold air is denser than hot it mixes better in the combustion chamber. Maybe it's just a wild guess/old wives tale or not.

rimfire,22