ITRCA

I change the oil every 3000 is this good enough or is syn the only way to
protect at 8,400

Search...."synthetic"......we have discussed this in extreme detail, you should find a lot of valuable information on synthetic oil here.

I don't think there is any reason to switch to synthetic. It's just not needed.

Synthetic oil offers excellent cold start protection for those of us that winter drive these cars, especially up here in the Great White North.
The fact that you can get a reliable 5w50 only in synthetic makes all the more sense.
Bottom line is, use the best oil you can afford and change it often.

Synthetic also provides better protection at high RPMs which our cars see often (At least mine does). I woudl recommend staying away from Mobil1 as it seems to be thinner than most oils and several people have burning problems. I woudl look into Amsoil, Redline or Royal Purple.

BBQd00d makes a good point too that use the best you can and change it often. Consider what you put your car through when judging your change intervals.

Trey

thanks again