oil and gas mileage

[iaspurchase]

Which oil viscosity will provide better gas mileage in a 2005 Elantra..or will
there be not difference? 5W-30 or 10W-30?
What the difference in using 5W-30 vs 10W-30 and can either have any
adverse effect on the longevity of the engine?

[WytchDctr]

the number to the right, 30, shows that the viscosity is once the oil is warm. Most of the time your driving with the engine warm right? I can see no real gain by running another Xw30 if your concern is gas milage.

[zx2uner]

Which oil viscosity will provide better gas mileage in a 2005 Elantra..or will
there be not difference? 5W-30 or 10W-30?
What the difference in using 5W-30 vs 10W-30 and can either have any
adverse effect on the longevity of the engine?

The difference would be minimal...you'd probably not even notice.

As for viscocity...where I live...I put in 10-30 in the summer since it gets so hot and thick oil is preferred when it's hot. So I was taught ;) I put 5-30 in the winter since we can get down to -30 and I want to make sure it doesn't get to thick to move around at initial start and warming up. You'd be amazed at the difference between 10-30 and 5-30 @ -35 deg f. We ran tests when I was in high school...and came to the conclusion that I'll put 5-30 in the winter.

Also, both can be used...check your books. I also don't think one oil will produce longer life...I may be wrong though...lol

Hope this helps.

[Soron]

Actually some oils are rated "energy conserving" on the bottle located in the api seal on the lower half of the circle on the back of the bottle (if you put an oil that is not api certified in the elantra it will invalidate your warrenty, i.e. redline or amsoil). Those oils will give you better gas milage than those that are not rated as such for the very same exact 10w30 or 5w30. It has more to do with the oils classification rating (i.e an sm rated oil is better than an sj rated oil for a given viscosity) but in general 10w30 oils tend to have that rating more than 5w30 and 10w40 or higher oils just plain don't have it, some better quality dino oils have this rating while most synthetics and semi-syn blends have it.

As for which is better for you, it depends on where you live, neither will not wear down an engine more than the other will, a 5w30 oil is suggested for colder climates (ie if it gets down below 30 or so degrees farenhieght in the winter use 5w30), while for people like me who live in a desert 10w30 is recommended (I should use 10w40 really but I don't wanna screw up my engine or lose the benefits of energy conserving oil). Just go with the automobile manufacturers recommendation range for oil (in the elantra its 5w30-10w30 I believe).

honestly you might get a 1 mpg increase if you used energy conserving oil vs non e.c. oil but I doubt it would make much of a difference for a 14 gallon tank, you would be better off getting synthetic where you tend to get 1-3 mpg increase anyways just from switching.

[littlepooka]

Actaully, in 2005 Hyundai started recommending 5w20 for all their cars.

There is minimal difference between 5w30 and 10w30. 10w30 is good until 0 degrees F. There will be no noticeable difference in gas mileage. Your best bet would be synthetic. But even then, you're talking MAYBE .25-.5 mpg.

[delacerda]

If you are following the "severe" schedule and changing your oil every 3750 miles, there will be no benefit to using a synthetic oil. For best fuel economy, I would use a 5W-20 SM GF-4 rated oil. UOA (used oil analysis) time and again shows these oils to be as good as any synthetic at this interval. Some oils that stand out are Havoline/Chevron, Motorcraft, TropArtic, and Castrol GTX. (However, most SM GF-4 rated 5W-20 oils provide great UOA) With an oil change interval of 3750, using any grade of SM GF-4 rated oil will provide excellent protection for many many miles, just make sure you use a quality filter!

[HYTECH]

Actaully, in 2005 Hyundai started recommending 5w20 for all their cars.


they only use 5w20 in the 06- sonata, 06-entorage 07- santafe/ 6 months ago my rep declined to warranty an engine for knocking because the customer had there oil changes at a ford dealership that used motorcraft semi synthetic 5w20 this car had 28,000 miles

[exsailor]

I had an oil change 2 weeks ago at the dealer (04XD GT) and they used 5w20 - I asked if it was a typing error on my invoice and was told that they use that viscosity on all the Hyundais from 04 on

[delacerda]

The manual for my 06 Elantra states that 5W-20 is preferred for fuel economy.

[cclngthr]

they only use 5w20 in the 06- sonata, 06-entorage 07- santafe/ 6 months ago my rep declined to warranty an engine for knocking because the customer had there oil changes at a ford dealership that used motorcraft semi synthetic 5w20 this car had 28,000 miles

Any particular reason why the denial?

I would think that the oil filter would be the issue rather than oil.

[quickfingerz]

The general formula is that you gain 0.2 miles per gallon on a four-cylinder engine when you go from 20w-50 to 10w-30. Someone on a civic forum did a test.

[HYTECH]

they only use 5w20 in the 06- sonata, 06-entorage 07- santafe/ 6 months ago my rep declined to warranty an engine for knocking because the customer had there oil changes at a ford dealership that used motorcraft semi synthetic 5w20 this car had 28,000 miles

I was wrong on this it is all hyundai vehicles 2006 and newer

the denial was on a 2004 or 5 tiburon 2.0l the rep said that in this vehicle the 5w/20 is only recomended for below freezing temps. and not for sustained high speed driving

to be sure on your vehicle look on webtech under shop manual click engine mechanical then lubrication then oil and filter replacement there is a chart that showes what weight oil to use some cars are under engine mechanical --general--then specs

[littlepooka]

they only use 5w20 in the 06- sonata, 06-entorage 07- santafe/ 6 months ago my rep declined to warranty an engine for knocking because the customer had there oil changes at a ford dealership that used motorcraft semi synthetic 5w20 this car had 28,000 miles

I know for sure that the 2005+ 2.7 V6 in the tiburon, santa fe and tucson require 5w20. And i'm pretty sure the elantra does too.

There has been a problem related to oil filters, there is a TSB out there for using aftermarket oil filters, basically the filters they use are too small and are causing knocking. You sure it wasnt for that?

[txdproject]

ok so im in chicago and im currently running 10w-30 sinc its already getting cold what should i be using ? anyone?