Owner's Manual Craziness

[sangyup81]

So I know a lot of you guys say use what the owner's manual says.

Well my friend's dad has a Hyundai Tuscon LX which has a 2.7L V6. The manual found in the glove says the following:

(all degrees are in F)

5w20: under 15 degrees only
30: 0 to 105 degrees
0w30: below 50 degrees
5w30: 0 to 50 degrees
10w30: 5 to 105 degrees
10w40/10w50: 0 degrees and higher
15w40/15w50: 10 degrees and higher
20w40/20w50: 15 degrees and higher

It also recommends use of 5w20, 5w30, and 5w40 to be "restricted by driving condition and area." It also warns against using 5w20 "for sustained high speed vehicle operation."

Now when I look online for a PDF of the manual, it says use 5w20 in all conditions for best fuel economy and to use 5w30 if you can't get 5w20. It also says 10w30 is ok over 0 degrees

One manual says 5w20 is dangerous in highway driving and the other says it's great.....

 

[beast3300]

5w30 winter, 10w30 summer and call it done.

 

[sangyup81]

I was ready to do M1 0w40 or Rotella T6 year round based on the original manual but the online stuff really threw me for a loop!

 

[Robenstein]

Id do a synthetic 5w30 in winter and Rotella T6 in summer.

 

[BobFout]

Based on that chart, 10w30 or 10w40 year round. That's assuming it's valid info.

Today's oils are multi-grade, no more changing oil based on season

 

[jmac]

Sounds like they took an old GM or Ford manual from 1980 something and copied it word for word in the oil selection section, then they found the newer US manuals and updated theirs to match.

 

[mechtech2]

Those charts are still in manuals?


Consider them useful mostly for warning us NOT to use thick oils in cool/cold weather.

 

[Bruce T]

I can't stop laughing. The Hyundai manual recommends every possible oil viscosity except 0W-20. I don't know anything about this engine's operating temperatures and clearances, but the UOAs I've seen for Hyundai appear to support the 30-weight oils over the 20-weight. Feel free to search the UOA section for "Hyundai" yourself. Besides seeking BITOG advice, you can also talk to your Hyundai dealer and perform your own UOAs.

I would lean towards 10W-30 in summer, and 0W-30 or 5W-30 in winter. I'm not sure how cold it gets in Maryland.

 

[SilverGGA]

Tough customers. You hated it when manufacturers put just one grade on the chart (5w-20 or 5w-30). You still hate it when they spell out all these choices.

 

[beast3300]

Originally Posted By: SilverGGA
Tough customers. You hated it when manufacturers put just one grade on the chart (5w-20 or 5w-30). You still hate it when they spell out all these choices.

True. Us BITOG'ers aren't satisfied with just simple charts or cut and dry numbers.

I am actually glad I joined here to see there are others that have a kind of OCD with their ride.