My dad and I use PowerService DieselKleen. It adds up to 6 cetane points depending on concentration. It's also ideal for filling up your fuel filter when you change it. It's in the grey bottle. They also sell an additive in a white bottle called Diesel Fuel Supplement which is an anti-gel additive and cetane booster, but it only boosts up to 3 points. They also have Diesel 9-1-1 which is an emergency additive to de-gel fuel. A good thing to carry during the winter.
Pros: adds 6 cetane points, ideal for fuel filter
Vehicle:
Volkswagen
