this could be a dumb question but oh well... whats the difference if i use 10w-30 instead of 5w-30? just tempature? will car run slower? faster? will it help the engine last longer being thicker?
5W30 is best for our cars.
- 2004 Cavalier - 124k, owned since new
my mechanic said with higher miles 10-30 is better. so it could be just an opinion thing.
4 door civic on the way
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i need a daily driver
Well, 10w-30 will get thicker when the out side temp increases, Also basically works that 5w/30w work out the same as 10w/30w, I would also recommend using 5w/30w for cavaliers, either way 10w/30w, will work just fine as well.
I use 10w/30 in summer and 5w30 in summer... Its probably doing nothing different, but I like to think it is!
Matt Linke wrote:I use 10w/30 in summer and 5w30 in summer... Its probably doing nothing different, but I like to think it is! 
5w30 for our car... all the time
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Buddy Club Ecotec Cavalier
* More to come *
Depending on the age of the motor, miles and wear and tear. The seals, fitment on components, etc. will start to deminish as time and miles goes on.
Its said to thicken the oil as the miles increase. (by 75k to 100k miles)
10w-30 is fine as long as it isnt in a new engine!
now DIE!
If you are running Synthitic run 10/30..If you go to the Gm dealer for your oil change they are just putting 10/30 in it because thats all the have in the big bin..10/30 is fine in this motor...They tell you 5/30 because it is suppost to give you better gas economy..But end of the day makes no diff for that..If your motor has high KM on it run 10/30..I have 140 thousand on my eco and its running 10/30 Mobil1 with no issues..
I run pennzoil sae-30 here in orlando all year long. i have 149,xxx miles. Running great!
when i first got my car soo many years ago i got the wrong oil the first time which was 10W30. i didnt want to change since it seemed ok so ive been using 10w30 for the past 4 years. it seems to work or i should say be more appropriate for my car with the weather that we have here also according to the back of the bottle when comparing. i dont have extreme cold or hot temps so i saw no reason to use 5w30. i do have a higher milage engine though.