I have ran 5W30 since I got the truck on 01. I was thinking of going to 10W30 since I don't drive the truck in the winter any more. Should I do this or does it matter? I have had no problems with the 5W30, just was reading what the different weights were for on the bottles. I run 10W30 in my GTP so it would be nice, just to have to buy one oil weight.

I run Mobil 1 FS if that matters

 

If the cap says 5w-30, then that's what you should use.
I've been using Mobil 1 5w-30 full synthetic after the 2nd oil change.
I recommend staying with what the engine calls for.

Jim

 

I am thinking this too. Just thought I would ask. It is really no biggy I guess!?

 

i have always used 10w30 and this is the only vehicle that i have

 

i use 10w30 m1. it's easier to find 10w30 than it is 5w30 where i live. so i guess thats the only reason i use it.

 

I use 5w-30

 

I would run 5W30 all year because that's what GM recommends. I tell you what...GM's design cues on their latest vehicles is not outstanding but they sure know how to design engines.

 

10w30 is the way to go as long as the climate you live in doesnt drop below freezing. (not a absolute rule, more of a rule of thumb) 5w30, is good for all climates, except for those extreme conditions.

I run 5w30 Mobil One 3 seasons of the year, and 0w30 Mobil One during those nice central Pennsylvania winters.

 

So will I hurt anything running 10w30?

 

i doubt it
but i just have a little v6 but i make sure it never thinks its just there to cruise around in