Hiya Walter!
Welcome to our little playpen! Which model RT do you have?
Is Amsoil a straight synthetic or a blend of the old and new? If it's all Lab-created, I wouldn't start using it until the motor is completely, thoroughly and totally broken in...
Filters?? I've seen ttem on EBay, but the dealerships are probably the best bet for them. I don't know of any aftermarket filters; I'm sure that they exist, but I just haven't started looking yet...
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2010 Blue RT Audio & Convenience model Se-5 transmision. Dealer-added foglights, accent LEDs and extra speakers. Some RTS chrome windshield, front spoiler and top trunk trim, RTS frunklight and frunk liner, Top Trunk liner, Chrome lower air deflector, fendertip LED bulbs and ISCI floorboards added by yours truly...