I know guys that swear by it and others that say lucas is a waste of money. All I personaly use is AMSOIL in my $printer 5W40 Euro and now in my 13 GMC SRW Unicel Amsoil 5W30 the oil lasts for 25,000 miles with an oil analisis done. I change my oil every 2/3 monthes depending where I'm driving and I live in Canada so no Cali to Boston lol