What oil for best fuel economy?

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i would say with large fleets (e.g. 100+ cars or nationwide) you could probably prove a statiscally significant increase in MPG when using ILSAC GF-4 or API energy conserving oils. That is what the whole CAFE argument is about.
 
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A 0W-20 Energy Saving Formula will give better gas mileage in most cases. I know that Mobil 1 and Pennzoil Platinum synthetics come in that viscosity. Some boutique oils with that viscosity are not energy conserving formulas, so make sure you verify that if improving fuel mileage is you main concern.
 

JHZR2

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One of the reasons to drive from 10w-xx oils to 5w-xx oils was supposedly to improve fuel economy a tiny bit during startup. You can get some help there. Generally, lower viscosity, lower HT/HS yields better fuel economy. As Mark said, a 0w-20 energy saving formula should give you benefits, and the syn oils may protect better in frings situations. The 20wt oils are also a bit more stable and robust in general, so you may not be giving up anything compared to a sheared 5w-30 dino, which may well be part of the design considerations for the engine anyway...
 
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 Originally Posted By: JHZR2
... Generally, lower viscosity, lower HT/HS yields better fuel economy...
That is what I experienced. Went from M1 0W40 to PP 5W20 and M1 0W20 gave me better than 3-4% gas mileage in both city and highway driving.
 
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Mobil 1 0W20 or PP 0w20. I would say any 0W20 that says it is good for a hybrid engine is going to be one of the better oils for improved fuel economy. AD
 

VicMatson

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No, I was reading another forum and saw that an oil can make a 10-15% difference. It jut seemed like an exaggeration. Are you guy's talking less? I drive a Corolla 50,000 miles a year so that's why I'm concerned. The poster said that going from PP to Valvoline synthetic got him those kind of differences. I'm cheep, so that's why I went from Mobile one to the Valvoline, but PP is on sale till the end of May at Advanced.
 
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JAG

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No way can there be a 10-15% difference in fuel economy between PP and Valvoline synthetic. It's a shame that someone would post such nonsense on the internet. Between non-friction-modified 15W-40 conventional oils and XW-30 synthetic, friction-modified oils, a few percent is what can be expected. Those are extremely different oils too, unlike how close PP and Valvoline synthetic are (assuming same viscosity grade). Both PP and Valvoline synthetic are very good. Whichever is on sale is what I'd recommend.
 

Bill in Utah

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I've got a 05 Corolla with 132k on it and have tried quite a few oils (from Amsoil, PP, Mobil 1, Mobil DC, Halvoline, Chevron, Pennzoil and others incl conventional and Syns) Very little to no difference. The best MPG (BTW, figured out over 5k minimum using same gas pumps with pen and paper) to date has been with Halvoline DS and Pennzoil conventional. Worst was Mobil DC and Mobil 1. All of them are close. Any one who is telling you 10-15% is full of it and prob trying to sell you (or justify) some oil brand. Even going from a 20/50 to a 0-20 would not get a 15% hit... Take care, Bill PS: All oils I've used have been the same grade 5w-30.
 

Patman

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Even if you found an oil that might give you a 1 or 2% increase in economy (which is doubtful) you'd also have to factor in how much extra that oil costs! If you have to spend $7 or $8 a quart to get a tiny increase, you're not saving any money at all compared to having bought oil for $1 to $2 a quart.
 
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I've experienced negligable differenes in fuel ecomomy with any oil. We usually average around 30-32mpg in the Corolla(3spd). The only time I noticed an increase of mpg was when ARX was IN the sump. Even then it was only 1-1.5mpg, but after the treatment it's about the same as before. When I buy oil, I don't buy it for fuel economy though. I buy it to keep our cars on the road :)
 

VicMatson

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I'm looking for a balance between OCI's,mpg, and the cost of oil. For example if PP gives me longer OCI's and I have to pay someone to change it, then even if it costs more I may be ahead even if it suffers from less fuel economy. At 50-60,000 miles a year knowing what my actual cost per miles driven can be important.
 
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i drive about 70k a year so i know exactly what you are talking about. i run 10k OCIs, and have recently started using 0w20 in my engines that call out for that (in the AUS manual, US manuals are useless for oil vis recommendations since CAFE). however, the other place that you can save a substantial amount on MPG is in your choice of tires. with my miata, i went from M1 0w40 to M1 0w20 at the same time i changed to a LRR (Low Rolling Resistance) tire. the combo was good for an 8-10% climb in MPG (from 25 to 28). when i went to snow tires for the winter (blizzaks) the MPG went back down to 25-26.
 
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Castrol whatever. Syntec blend 5w20 and syntec 5w20 are the best in my focus.
 
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 Originally Posted By: VicMatson
I'm looking for a balance between OCI's,mpg, and the cost of oil. For example if PP gives me longer OCI's and I have to pay someone to change it, then even if it costs more I may be ahead even if it suffers from less fuel economy. At 50-60,000 miles a year knowing what my actual cost per miles driven can be important.
Since you drive up to 60k miles a year that means mostly highway miles and you pay someone to do oil change, you should consider M1 EP. With M1 EP you can get away with 15k miles OCI and you need to do only 4 OCI's a year.
 
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Pump your tires up to the max recommended tire pressure on the side wall of the tire if you want max MPG. Now, the ride quality will probably suffer.
 

VicMatson

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 Originally Posted By: HTSS_TR
 Originally Posted By: VicMatson
I'm looking for a balance between OCI's,mpg, and the cost of oil. For example if PP gives me longer OCI's and I have to pay someone to change it, then even if it costs more I may be ahead even if it suffers from less fuel economy. At 50-60,000 miles a year knowing what my actual cost per miles driven can be important.
Since you drive up to 60k miles a year that means mostly highway miles and you pay someone to do oil change, you should consider M1 EP. With M1 EP you can get away with 15k miles OCI and you need to do only 4 OCI's a year.
I have used Mobile EP for years, but it scares me a bit. If you have a new engine it's great, but in an older one it gets black at around 6-7,000 miles or so. I also have to say that I buy cars at auction with about 80,000 miles on them before I get them. Lately though I have been using a pump to evacuate and change the filter every other time. My complex doesn't allow DIY maintenance. Last time I rented a rack at a DIY place and did a trifecta. Oil, coolant, and transmission fluid at the same time witch took me less that an hour. I get the impression the service franchises hate me now.
 
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