5w-30 Or 10w-30

[R Gage]

the oil cap says 5w-30 but in California I see 32 degree weather maybe 5 times a year and 100+ 40 days.Can I run 10w-30 without damaging anything, is there an advantage with 5w compared to 10w. I have 20k on 04 Sierra truck and 50k on 04 Yukon I am using castrol syntec in both.Thanks for any input.

[Draenor]

5w-30, like the cap states.

[96chevy7.4L]

Yes the cap states 5w-30. I run 10W-30 Mobil 1 full synthetic but that is my preference. The 10W30 will tend to stay a lil thicker even in the extreme heat. However it will be a lil thicker in the winter time. Being that you aren't in Alaska or Montana or even northern canada it wouldn't matter in my opinion. I am sure someone will chime in soon.

[lowrider]

I'm in Arizona and also run 10W-30 in my cars and the truck. When I lived in California I did the same thing. When I lived, for a short time, in Virginia I ran 5W-30 because they have a winter back there. And, as with my friend above, that is my preference.

 

Lou

[txab]

5w-30, like the cap states.

 

+1

[davzog]

My nephew is a certified Ford mechanic in Dallas with a lot of 100+ degree weather....he insists that Ford's recommended 5w20 works in all temperature and provides excellent protection...so, I stay with 5w30 for the GM 6 liter....just my $.02

 

Seems to me that the GM engineers are smarter than I am...ha ha

[WaterGuy]

Usually there is a chart in the owners manual that gives temp ranges and related oil weights.

But like most things in life, it is a suggestion.

[95Sierra2500]

The difference between 5w30 and 10w30 is the viscosity at cold start-up. 5w is a little thinner at startup. At operating temperatures (regardless of external temperature), the viscosity is the same.

[66nova]

5w-30 Valvoline Synthetic for me and I live in TX

[WilliamBos]

5w-30, like the cap states.

 

+1

 

 

+2. I run 5w30 syn year round. Never had an issue. And yeah, it does get hot here in the summer.

[Zembonez]

5W30 Synthetic for me. These engines are built with tight tolerances and you need the 5 weight at startup... especially in cool weather.

[dlstewart01]

10W30 will work fine for you. After all as was posted already both are 30 weight @ operating temperature. The difference between 5 and 10 is very small.

 

Some day I am going to compile a chart of engine tolerances over the last 15 years. personally I don't believe they have changed....but I have no research to post so i can't say that. What has changed is better technology and the ability to stay within the tolerances.

 

Europeans still run heavier oil than us. I believe the reason the 5W30 and 5W20 in the USA is for cafe (gas mileage).

 

I'll give you an example. The Corvette plant is only 45 minutes from me. the last time I was there. Z06s were coming off the assembly line. The ones for the USA had a label by the drivers door that said use only 5W30 oil. There was one coming off the same line, same engine headed for New Zealand that said on the label...use only 5W40.

 

I my self use German Castrol 0W30. You may say wow that is thin. Actually it is close to a 40 weight. API gives a latitude in weights and there is over-lap so all 5 weights or all 30 weights are not the same. It depends on the manufacturer. All this can be found on the oil manufacturers web site.

 

http://www.bobistheoilguy.com/index.php?op...8&Itemid=55

 

Right out of the GM manual...

 

[pm26]

5W30 Synthetic for me. These engines are built with tight tolerances and you need the 5 weight at startup... especially in cool weather.

 

Really? Even the ones with a severe case of piston slap?

 

BTW, I also use 5W30 and I live in hot and humid Florida. There in no winter to speak of here.

[Zembonez]

5W30 Synthetic for me. These engines are built with tight tolerances and you need the 5 weight at startup... especially in cool weather.

 

Really? Even the ones with a severe case of piston slap?

 

BTW, I also use 5W30 and I live in hot and humid Florida. There in no winter to speak of here.

 

Piston slap has nothing to do with lubrication and everything to do with piston skirt design. That's why engines with the problem still run hundreds of thousands of miles. I'm sure it is annoying, but it isn't a reliability issue.

[Black02Silverado]

5w-30 year round with no issues. It is a 30 weight. For California weather you can use either one. I just run 5w-30 year round.