in your CLS. I am planning to use 10w-40 Valvoline Synthetic blend in my car. The reason I am chosing this weight is because I live in Laredo, TX very close to the Mexico border. The range temps range between 90 to 106 degrees in the summer and the winter, which starts for us around Nov. and last until the end of March ranges between 55 to 86. Does this choice seem to be right? I feel that the 10w-30 is to light. Any opinions regarding this dilemma.


Thanks in advance

 

I don't see any problem! ...In fact, I've noticed a lifter "ticking" from this thin 5w-30w oil; especially in the summer heat. Also, I think that synthetic oils flow better than dino oil!

I've always run Castrol 20w-50, and I've even considered it!

 

In Texas 10W-40 is an excellent choice, especially Synthetic. Just don't get carried away and change it every 3,000 miles (such a waste). YMMV

 

isnn't 10-40 too heavy?

 

Not with the high temps that I get down in Laredo TX. Avg temp is b/w90 to 106 degrees in the summer and winter is very short for us down here.