Hi bud, welcometomyturbodies. Mine takes the 15-40w too and it's also a 2000 model. I've read a lot of people use the synthetic but don't know if it's worth it on our older cars. I would've thought it'd be more useful on some of the newer tdi's. I'm sticking with the 15-40w myself for now and doing my regular oil changes.
VW TDI forum, Audi, Porsche, and Chevy Cruze Diesel forum
A forum community dedicated to Audi, Volkswagen, Porsche, and all turbo diesel owners and enthusiasts. Come join the discussion about performance, modifications, troubleshooting, TDI, maintenance, and more!