quote: Originally posted by farrarfan1: Millions and millions of cars survive millions and millions of miles on 5W30 and 10W30 in climates a lot hotter than New Jersey. What makes your cars and or driving conditions so different that you're "uncomfortable" with 10w30? And why are synthetics not an option? Do you believe a conventional 20W50 is better for your cars than a good synthetic like Mobil 1 or Pennzoil Platinum?
I think I read a post here where a guy said he used 20W-50 in his Beamer near Buffalo, NY all winter, and had no problems...
I still wouldn't recommend it though...
*edit*
I wouldn't go higher than a quality HDEO 15w40, but 10w30 will suffice nicely. I'm using 10w30 HM Valvo MaxLife in my 1990-vintage 3800, then going Valvoline MaxLife 10w40 in July...