Hey whats up? hows everybody doing? Ok I got my Oil Changed today. I went from a 5w30 and this time I put a 10w30 which the people who changed my oil said was probally better for the engine. I always hear 5w30 is but I Live in California so he said 10w30 would be best? What do u think? its "Pennzoil" brand with the Pennzoil Filter. Tell me what u guys think?

 

im not a big pennzoil fan.....i use castrol gtx 10-30 w/ a k&n oil filter.........

 

whats wrong with Pennzoil? and I Also heard Castrol was good.. But thats the only oil they had at the shop.... I Dont change my own oil

 

They just gave you slightly heavier oil, thats all. You won't see much of a difference between 5w30 and 10w30. But it's best to pick one brand and weight and stick with it.

 

I've run Pennzoil in many of my vehicles and haven't had any problems. It is just a matter of preference. As for the weight, it isn't a big deal. Some oil change places only stock one viscosity and that is what they use in all vehicles other than diesels of course. The dealer I used to work at only stocked 10W30 and we used that in cars requiring 5W30 or 10W30.

 

10W historically will shear slower than 5W. With the new oil specs that could change, but that's how it's been in the past. The LT1 does like a bit thicker oil than a 5W so yes generally speaking you're better off with the 10W in a warmer climate.

Pennzoil is a good oil. I dunno what the Pennzoil filter is like but if you're changing at 3k intervals there aren't many oil/filter combinations that will be much worse than the next.

BTW beware of opinions on such topics on this board.

 

5w-10w doesn't mean as much as you guys seem to think, some of the best oils judging by actual anaysis for the LT1 are 0w, some are very thick 30wts. and some 40wts.. 10w-30 is fine in most brands but don't delude yourselves into thinking it is much different at operating temps than a 5w-30. M1 at least the 10w-30 is actually thinner at tempature than the 5w-30, and the at temperature viscosity is most important seeing as the oil spends more time with the engine running at those temps.

 

5w and the 10w is referring to the oil wieght at cold starting. Once you are at operating temp, they both are a 30w oil. There is No difference.

 

There certainly can be a differnce, 30wt. is still a range not a precise viscosity. I do agree with the spirit of your post though in that that number is far more important than the first. The owners manual states 10w is appoved down to 0F so for most of the year 10w is fine for most of this country.

 

Good Link.

 

One not followed often enough either. This forum is often a poor source of oil info the one you linked is almost THE source for GOOD oil info.