about to change my oil, they didnt have 5w30, and told me i should be using 10w30. is this cool to use at 91K?

 

sounds fine to me...I generally run castrol 5w30...but 10-30 will be just fine

 

the _w 30, just effects the cold viscosity, so unless you are below -20 degrees f, you should be good to go.

 

You should be fine. Most on here run 0w40 or 10w40 synthetic

 

viscosity yes, but the temp rating is the first number... on a higher milage car it is reccomended to use a heavier weight oil like 40... mobil1 0w40 is what i use regardless of milage just to try and keep any ticks or knocks away...

 

right on, i'm nowhere near 20 below so i guess im good.

 

I always like 5w40 chucky....0w40 is good as well. Did I say synthetic?? .