I have a 2013 Winnebago Sightseer 33C with a Ford F 53 chassis and a V10 Triton gasoline engine. I changed my oil about 4000 miles ago with Amsoil XL 5W-20 and a Wix 51372XP oil filter. It has been over 10 months since the change. I am planning to change the oil and filter at one year. Does anyone see a problem with this frequency? Some folks are telling me to change out the oil filter now and keep the Amsoil in until 10000 miles have gone by. They said that the oil is fine but a Wix filter should be changed out at 5000 miles or 6 months. does anyone out there have any experience with this. Thank you.