I just purchased a new (2003) Chevy Impala LS.It has the 200HP 3.8V6 .The oil filler cap and the owners manual both say to use 10W-30 oil.They do not specify or say to use Dino or Synthetic. In my other cars ( late 60's BBC Chevelle and a late 70's Olds 305 V8).... I have been useing Kendall GT1 oils with as best as I can tell great success.Both run great. The typical ambient air temp in my region is lows in the 40's F and highs in the summer in the high 90's F during the summer.Only a couple nights a year during winter will the temps even get into the 30'sF at night...So it really doesnt get very cold here. I live only a few miles from work and never need to hit the freeways to get there.So it's alot of side street stop and go driving. This engine has only around 400 miles on it and would like to get the origional oil out and change the filters...Both air and oil.... very dusty at work....I have to admit I do change change the oil and filters frequiently in my other cars.Will definatly do the same with the Impala. Can someone suggest weather the Kendall GT1 that I use in my other cars is ok for this use or should I use something else? A store around the corner from work carries Fram and K&N filters...or should I use Wix or OE filters ?? Any help appreciated...Thanks.