According to the owners manual on my 06 the recommended oil viscosity is 5w20 under all conditions. I know the Queensland climate is warm, but Arizona in the US is comparable and that is what Ford recommends. I would assume that would apply regardless of whether you were in Queensland or Tazmania, jetford. From what I understand the oil passages in the heads and valvetrain are too small for heavier viscosty oils to pass through in adequate volume to properly lubricate. The owner manual also states not to use any oil additives. Doing so can void the warranty if there is any warranty left.

 

Thanks heaps for your input much appreciated we will be trying this tomorrow as we are the Total/Elf Lubricants Importers/Wholesalers for North Qld.

 

I would stick to the 5/20 semi syn. After a few oil changes to get all the lucas out my truck runs great now. I use kendall its cheap and has alot of good reviews so i can change it every 3-5000 kms without breaking the bank

 

I was running synthetic blend until last year when they raised the price to within $5 per 5 qts. US of Mobil 1. Now i'm running Mobil 1 synthetic.