Hey guys. For the next 6 months I'm going to driving about 1000km a week. The 2 dealers I have called insist I need 6 mo or 6000km service intervals unless I change to synthetic. I'm really trying to avoid every 6 week oil changes as I don't have the time. Question is, can I go longer without voiding my warranty? I've read on here people going longer than that. Thanks.