What oil for my 05 or does it matter??

 

Winter time in Ohio you should use 5W40. You can get Rotella and Mobil1 at Walmart in 5W40. I prefer Mobil1 and just changed my own for the winter, but I run it year round.

 

When making the decision to use synthetics such as a 5/40 or 15/40 Amsoil, you should also consider utilizing a high quality filter with synthetic media. Two filters that many DTR members prefer are the Fleetgard Stratapore or Donaldson Endurance ELF 7349.

 

Either one is good, it's really up to you. The 15w-40 HD Diesel and Marine oil is good down to -44, and the 5w40 CJ Premium Diesel oil is good down to -51. Personally, I would run the 15w-40, mainly because I strictly steer clear of any CJ-4+ rated diesel oil for a pre-emissions diesel engine. I have run the 15w-40 w/ Amsoils filter in my 01' Excursion w/ the 7.3 for the past 2 years and change the oil once a year, about 12k miles. After each time I have sent the used oil off for analysis and every time it has come back perfectly fine.

 

15w-40 is cheaper than the 5w-40, at least Amsoil anyway.