Originally posted by Dallas4u
I use 5w-30 Mobil 1. I also have the Amsoil filter and a K&N drop in filter. The Amsoil filter seems a little large, but is spongy, and you have to cram the top of the OEM air box over it to get it fastened. The K&N fits nice and neat, but may let more dirt in than the Amsoil (as many people have seen the studies online and in magazines).
Are you talking about the air filter? I was talking about the oil filter.

Here's the part number for the oil filter: Amsoil SDF-36 - Super Duty Full-Flow Engine Oil Filter (SDF)

Sveltax, check the owers manual... best way to chose oil weight is by the temerature range your VX operates in (i.e. the climate in your area). Too heavy of an oil and you'll performance. Too light you'll risk breaking down the oil sooner (which negates the use of synthetic oil).