Fuel Economy Gains for Different Weight Oils
- Thread starter Gene K
- Start date
- Status
- Joined
- May 27, 2002
- Messages
- 624
I have a 99 Nissan Sentra that has been run with 10W-30 since new. I never closely checked gas mileage in town but always kept very close track of it on highway trips. I always got 31mpg. In April I changed to Schaeffers Blend 15W-40. I immediately took a cross country trip of 6,020 miles. On this trip I got 34.95mpg. I changed the oil, changed to Schaeffers ATF and used LC and FP.
Can Happen. To make it simple, it's all about the oil. some 10w40s or 15w-40s will give better mpg..
TRY this: Take a random sample of say 5 or 10 oils.
Run them at least one if not two or three OCI's
Then find the MPG of each one.
They may be close on some and others a real change... as much as 1-2-3MPG .
I have had dino do as good or better than Syn or Semi-Syn blends.
It's all about the oil.
Just like some oils will provide a longer drain, and others clean better, etceteras. Each blend has its unique nature/it's own signature if you will and the MPG is no exception.
TRY this: Take a random sample of say 5 or 10 oils.
Run them at least one if not two or three OCI's
Then find the MPG of each one.
They may be close on some and others a real change... as much as 1-2-3MPG .
I have had dino do as good or better than Syn or Semi-Syn blends.
It's all about the oil.
Just like some oils will provide a longer drain, and others clean better, etceteras. Each blend has its unique nature/it's own signature if you will and the MPG is no exception.
- Joined
- Jun 2, 2003
- Messages
- 23,591
Unless you drive your car on a test track under the exact same conditions, how could you notce a differnce of a maybe a couple percent in fuel economy? I know that if I do just one jack rabbit launch, I'll screw up any attempt at even getting anything close to normal averge mileage for that one tank!
Well for my 2cents worth I went from 20w-50 castrol gtx in my oil burning cressida to 10w-30 chevron supreme and there was a major difference in gas milage. I check every tank and my trip to work is very consistant. Best I ever got with castrol was 19.75 but I could get a consistant 22 with the thinner chevron. So in my mind it does make a difference.
- Joined
- Sep 28, 2002
- Messages
- 39,799
That's the way it is on my 02 Jeep SE (2.5 4banger auto). If you drive it STRICTLY like an economy minded driver (nothing over 60 ..just ease the gas out of the lights and let the high stall converter bring the vehicle up to engine speed ..let the lock up work at the minimum speed ..etc.) you'll get 20-21 mpg on my suburban to work 44 mile per day drive. Use the a/c or be in a hurry JUST ONE LEG of the whole week and you'll be down 2-3 mpg. My daughter, if she drives it, can bring it down to big block range (12-13).
My 92 Caravan is totally different. You can drive it just about any sensible way you please and be "normally spirited" in technique ..you get 20 (which is what it did new) ..if you go fuel squeezer ..you can get 22 ...but it baselines so close to the peak. Long trips @ 75 yield about 22.5. It's rather numb to driver input as far as economy. Same with my daughter's 91 Taurus (about 26-27).
Doubters can doubt, but I had 120,000 miles on 5w-30 and have a record of each drop of gas used in the last 2 years +. I've had the 15w-40 in for > 7,000 miles, have gone through numerous tanks of gas and ALL are higher. NOTHING else was changed.
Dave
Dave
I'm wondering if you had excessive blow-by that the 15W40 reduced, increasing the effeciency of the engine. I could see no other logical reason for an increase.
Patman
Staff member
I couldn't believe the difference in MPG in my wife's Civic between her driving and me driving it. She averages 24MPG in her commute with the car (all city, lots of stop and go) and all along I thought something was wrong with the car. But this past week I was the only one to drive it, and did all city driving with it (no rush hour though) and I got 36MPG with it! She puts her foot to the floor a lot though, and even though I drive my Firebird that way, this week with her car I drove it pretty gently since my son was always in the car with me.
So as you can see, the same vehicle with different drivers and different traffic conditions can show vastly different numbers.
So as you can see, the same vehicle with different drivers and different traffic conditions can show vastly different numbers.
No, it's true. You can have increased fuel economy with a heavier weight oil. The CAFE chart can simply be used as a rule-of-thumb reference.
In other words, different brands can contribute as every oil has a different inherent coefficient of friction as well as the fact that different weights work better in different engines...eg. ring sealing contributing to increased engine compression.
In other words, different brands can contribute as every oil has a different inherent coefficient of friction as well as the fact that different weights work better in different engines...eg. ring sealing contributing to increased engine compression.
Agree. But it just doesn't have to be a different weight oil, the blend itself makes or breaks the performance. But YESS , I agree!!!
It's all about application, but in the end the OIL for the right application is what is the difference!
- Status
Similar threads
