Using heavier viscosity oil to increase fuel economy?

[jamescartagena]

So far getting 38.89 mpg average for the last 3500 miles. Traffic is getting bad ever since Labor Day so it is difficult to get the same driving conditions I was getting earlier in the summer. Not bad considering it is taking me about 1/2 hour more each day to get to work.

Plan on trying a thinner oil next oil change. Havoline 5w20 (Gets good reviews and UOA's on BITOG)

[GasSavers_smoke]

I think thinner engine oil can reducing restriction with the
internal movements.
New cars can alway use thin oil to get better MPG,
but as for old cars, because the pistons and rings are not
seal tightly as new car,so thicker oil can helps get better
compression, also more power.

[JanGeo]

Stop playing with your engine oil and switch to Synlube once and for the life of your car you will not have to change your oil again and get better mileage and less wear.

[MetroMPG]

Okay JanGeo, I'll bite.

Can you point to a controlled study that supports the fuel-saving claims of SynLube?

[JanGeo]

Yeah look at my gaslog graph - read the info in their website - besides right off the bat you save by not having to change your oil again for 100-150,000 miles which should cut your oil cost in half at least and save you tens of hours of time.

[jamescartagena]

I would love to try Synlube but at 32 dollars a quart is the initial shocker for me. Plus I like to change my oil. How many miles do you have on your oil?

[JanGeo]

Originally Posted by jamescartagena

Plus I like to change my oil. How many miles do you have on your oil?

Sounds like you have been brain washed by the auto and oil industry . . . LOL
. . . m u s t c h a n g e oil!
Right now 7839 miles and I put it in at about 3800 miles after initial breakin so 4,039 miles give or take a few miles. Level is exactly the same and it looks as black as the day I put it in. Yesterday I bump started it in second gear going about 1.5 mph - it started right up - just popped the clutch out and in again as fast as I could move my foot. Started better this way than with the starter motor.

[MetroMPG]

Originally Posted by JanGeo

Yeah look at my gaslog graph

Ahem - "controlled"?

No offense, but the graph proves nothing one way or the other about Synlube. It's of a vehicle which was breaking in, in ambient temperatures that were rising, driven by someone who wants to get good fuel economy. (And is getting great FE, I should add!)

I don't doubt your MPG numbers. I just don't think you can authoritatively say that based on your graph, Synlube raises MPG.

read the info in their website - besides right off the bat you save by not having to change your oil again for 100-150,000 miles which should cut your oil cost in half at least and save you tens of hours of time.

Cost savings aside, I'm really just interested in the FE claims.

I had a look on their site and couldn't find any mention of a controlled study for replacing crank case oil in a passenger vehicle and its effect on FE.

Replacing diff-oil in trucks & heavy equipment with synthetics is different, and known to have a small FE benefit. That *is* mentioned.

I was just curious if you had more information is all.

[JanGeo]

They say about an 8% increase with the engine lube then the power steering lube was a few percents and the tranny will vary with what was in it originally. Apparently EVERYONE that changes the tranny oil in the Scions sees mileage improvements when they change to a "better" lube. . . I.E. Redline - Mobile1 etc.
One thing I did notice was that the idle gets down to 0.1gph and about 650rpm but after some extended driving around the idle gets higher like about 750-800 and still 0.1gph so yes the engine is still breaking in a little but is averaging about 10mpg more than EPA estimates (33% more).

[rh77]

I hope I'm not too late on this one -- I once heard - no validity, just hearsay - that you're asking to blow-out the seals and gaskets with a significantly higher viscosity than needed. Would the oil pressure increase with the thicker stuff? A guy used to insist on 40W oil for his engines (this was for the old carbed cars). The guy got a newer, fuel injected car, insisted that the 40-weight oil be added, and it blew the living daylights out of the engine.
RH77