I have a 6.4L Powerstroke in my 2010 F-250 FX4 XL long bed Supercab and have been using Shell Rotella T6 in it since I got it. A friend of mine told me about a test of oils on YouTube and said that Mobil 1 is a better synthetic oil at temperatures below freezing. I live in Colorado along the base of the Rockies and we get lots of snow with temps in negative numbers in the early morning in the winter.

I am now thinking about switching to Mobil 1 5W30 but want to know what you are using and why?

 

Mobil 1 5W-40TD is what I've used for 119k and counting with no issues.

 

I have also used the Mobil 1 for 37,xxx miles. I switched to it at 5,000 miles when I did the first oil change, currently at 42,xxx miles now and have no complaints. UOA's come back great as well. I will be switching to T6 next oil change seeing as how i have about 20 gallons in the garage from when tractor supply had it on sale for $15.97 a gallon and the rebate was going on, couldn't pass up that deal!!

 

i am interested in what your UOA's will say after the switch slowmans

 

It will be about a year..lol...I only put about 6,000 miles a year on her....

 

I haven't used 5w30 but i have used mobil 1 full synthetic turbo diesel 5w-40 for a period of just under a year in a few of your truck tractors with cat and cummins engines. What i found in the cooler weather around 20-40 degrees the oil worked fairly ok, in the summer it was horrible in our vegas heat of 115-120 during the summers. Oils temps ran noticeably hotter, the oil broke down fast looked like water when you preformed a PM. Schedule oil samples showed the TBN very low not allowing us to run extended intervals. I was not impressed and switched back to 5w-40 T6 Rotella synthetic.

The measurable engine wear did not seem to go up or down looking at the samples but the additives seem to fail fast as a result the oil broke down fast limiting us from running extended service. All our trucks are equipped with by-pass filters and we typically run oil well past 50,000 miles providing oil samples are good and the TBN is still in acceptable ranges. This is a problem we have never experienced with the Rotella T6 Full synthetic 5w-40.

I am a big fan of mobil 1 synthetic oils in gas engines, matter a fact its all i run and have never had any issues in gas engines. I really don't know why the oil wouldn't perform well in diesel engines but personal experience shows it does not in warmer weather I'm not sure how well it does in low sub zero temps.

 

Excellent info SandDemon, thanks.

 

Hi n4rpd,

The Shell Rotella T6 5W-40 full synthetic heavy duty diesel engine oil is the perfect choice for your Ford 6.4L Powerstroke. This oil is approved per Ford diesel spec, WSS-M2C171-E. In addition, Shell Rotella T6 5W-40 Synthetic engine oil is based on a free flowing ,synthetic base oil that allows reliable pumping on start-up under cold climate conditions yet remains thick enough under high temperature operations to protect against wear.


-The Shell Rotella Team