Zambee500
Veteran Member
This might be a risky thread to start, but here goes: are these about equal for a PD motor in the summer, or which one of these would be better for high ambient temperature use? From what I've gathered here over the years, T6 is a bit thinner than TDT and it makes T6 a great choice in the winter up north for cold start-ups, as well as marginally better MPGs with T6 than TDT. And TDT gets the nod over T6 for longer drain intervals (although T6 is fine for 10k miles).
Does that mean conversely that TDT, being a bit thicker, would be better in the summer in the South with high outside temps? I noticed Shell advertises T6 specifically for high-temp operation, but not sure what to make of that so I thought I'd ask the experts. For the past several years I've run T6 in the winter and TDT in the summer, and then whichever in the shoulder seasons. Just double-checking that philosophy as it's time for another oil change and where I am we've got 2 more months of 90+ degree weather.
Also, how do the characteristics of Delo 400 LE compare to T6 and TDT? On the thicker or thinner side? And 10k vs. extended OCIs? Other differences?
Does that mean conversely that TDT, being a bit thicker, would be better in the summer in the South with high outside temps? I noticed Shell advertises T6 specifically for high-temp operation, but not sure what to make of that so I thought I'd ask the experts. For the past several years I've run T6 in the winter and TDT in the summer, and then whichever in the shoulder seasons. Just double-checking that philosophy as it's time for another oil change and where I am we've got 2 more months of 90+ degree weather.
Also, how do the characteristics of Delo 400 LE compare to T6 and TDT? On the thicker or thinner side? And 10k vs. extended OCIs? Other differences?