quote:Well depends it is synthetic or not. A petroluem 10W-30 starts to harden even at about 25*F. A good synthetic 10W-30 will still be good down to about 5*F with original fluidity. The wax crystals in regular oil cause the winter abilities to drop alot. Synthetics naturally have better cold start properties. But if at all possible, try to use a 5W or lower becuase you can only benefit from it even if you will never see temperatures belowe 0*F. Shear stability isn't really a big issue with synthetics anyway. So i guess my real question is what kind of oil are you using??
Originally posted by haley10: Most top brand 10W-XX should be fine to zero F. What is recommended and what do you have in there now?? Did you have a slow start or something???