Originally Posted By: bmwtechguy
From what I have seen in UOA, they both work well. The CI4+ has been around longer with a longer track record in more vehicles with more UOA's. There is some talk of TDT being a lower grade of CJ4 than the Delvac 1 found in gallons at truck stops, not to mention, a very big difference in gallon price between the two. Previously these were both formulated the same.
So, my choice would be the CI4+ if my vehicle did not require CJ4. Especially if I could get it cheaper.
I'm curious where you heard that from...previously TDT and Delvac 1 were the same, it's odd why Mobil would change it?
Just cur