5W-20 vs. 5W-30

[walk23]

Switched from 5w30 to 5W-20 PP hoping to improve millage in my 2006 Toyota Matrix XR. Noticed that the RPM's were a tad higher and the temperature gauge ran too a tad higher With the lighter oil I would have thought there would be a MPG gain but it looks like the engine is working harder.

Searching for comments before I switch back to 5w30. The car has 150K on it and has used Synthetics 95% of the time.

Thanks

 

[lexus114]

That`s strange? we have guy`s on here that use 5W20 in a 5W30 spec motor with no seemingly ill affects. And most 5W30`s shear down to a 5W20 anyway. Maybe the Texas Heat is a little too much?

 

[cchase]

Temperature gauge has nothing to do with viscosity, it's controlled by a thermostat.

May I suggest it's all in your head?

 

[walk23]

Thanks, just thought rpm increase would indicate that the engine is working harder.

 

[aquariuscsm]

Maybe the thinner oil isn`t creating a large enough boundary between the moving parts thus generating more internal heat? Something I`d never do is go thinner than specd.

 

[Steve S]

Ford engineers realized about .01 to .02 mpg improvement between the 20 and 30 wts. that is probably at the best.

 

[pbm]

Maybe the RPMs are a tad higher because the thinner oil allows the engine to spin more freely?
I do believe that the Matrix (Toyota) was respec'd for 5w20 but I would probably stick with 5w30 in summer.
I plan on using up my 5w20 in my 2008 Corolla in the winter.

 

[TFB1]

You guys that use 5W-20 for the recommended 5w30 in hot climates are just kidding yourself, you won't see any improved mileage and may not have enough protection for your engine... Regardless of the popular belief, in most engines a high ambient temp will increase oil temps...

If you are just croozin' a half mile up to the 7-Eleven every afternoon for a six pack, the 5W-20 would be a good choice, but not on the interstate running 80Mph...

 

[webfors]

Stick with the 30 weight and don't think about it again

 

[walk23]

Going to do just that webfors. Thanks

 

[MuzzleFlash40]

Ive own'd a few of the big body fords from the 90's models all the way to the 2006 I have now. I've always wondered if it would be better to run the 5-30 oil in the new engines, even though they call for 5-20.

 

[1999nick]

Originally Posted By: walk23
Thanks, just thought rpm increase would indicate that the engine is working harder.


The only reason for an increase in rpm is that you are going faster.

 

[JOD]

Originally Posted By: TFB1
You guys that use 5W-20 for the recommended 5w30 in hot climates are just kidding yourself, you won't see any improved mileage and may not have enough protection for your engine... Regardless of the popular belief, in most engines a high ambient temp will increase oil temps...

If you are just croozin' a half mile up to the 7-Eleven every afternoon for a six pack, the 5W-20 would be a good choice, but not on the interstate running 80Mph...


There's one way to tell--pull the oil temps when you're driving. In my car, it makes no difference in oil temps up to ambient temps of about 100 degrees, cruising on the highway at 80mph, driving over mountain passes... I really never see temperatures higher than that, so above 100, I have no idea what happens.

 

[JOD]

what do you mean "rpm's are higher"? At idle, or driving?

If it's while you're driving, oil viscosity isn't going to have anything to do with that unless you're driving faster--unless changing your oil magically changed your gear ratios?? What am I missing here?

 

[walk23]

@ 70 MPH, 2900 RPM vs 2800 RPM

 

[lexus114]

Just curious; does it seem to run any different other than the rpm thing?

 

[walk23]

It ran strong but at 70 miles an hour I noticed a slight rpm increase over the 30wt.

 

[JOD]

Originally Posted By: walk23
@ 70 MPH, 2900 RPM vs 2800 RPM


OK, thanks. Well, your engine RPM at a fixed speed hasn't increased, unless you've changed your tires. Neither has your coolant temperature, unless you've changed your thermostat. So, if you're gauges are telling you that both of these things are the case, we're left with it being an artifact of the gauges.

Are there any other variables--did you clean your battery terminals or do any other maintenance. The only thing I can say with 100% certainty is that engine RPM's are not related to oil viscosity. As far as engine temperatures, it's almost certain that OIL temperatures are lower, not higher--water temp is dependent on your cooling system, and is what the gauge tells you.

 

[tig1]

RPMs are controlled by the computer and the gearing you have, not oil. If anything thinner oil will slightly reduce oil temps, but will do nothing for water temp. Also I started using Mobil 1 5w20 in 1978 in engines spec'd for 30 & 40wt oils. No problems.

 

[ARCOgraphite]

Reads like a transmission problem if verifiable. Isnt the xR a high output yamaha engine? Proceed with caution. Toyota VVTi in my old 1nzfe is sensitive to viscosity.