Is a 5.7 HEMI actually that delicate?
Nope. We have a small fleet of them at work with about 200,000 miles on each of them, bulk NAPA 5w-20, NAPA filters. These trucks don't have oil coolers and are driven hard and put away wet. Amusingly, we lost one of the most gently driven ones to lifter failure last year (which is a materials issue with the lifter, as discussed in a previous thread, GM has the same issue) while the others are all running fine.
Like many trucks (Ford, Toyota), exhaust manifold stud failure has been a common issue on the DS trucks. It's too early to tell if they've done anything about it on the DT's. We had them all replaced in a package deal a few years ago (almost the entire fleet was ticking) by an amazing tech who I recommended to another member on here who used the updated studs and they've been quiet since.
At least with the HEMI, the manifolds themselves are reusable. On the Ford modular, the manifolds typically crack and getting replacements now has become quite difficult. My dad's passenger side on his Expedition is cracked again and leaking and the Dorman ones don't seem to last like the OE Ford ones do.
We have a 4Runner that belongs to one of the PM's that had the same problem and I guess it's extremely common and a real pain to change them. The OE Toyota manifolds are also insanely expensive, while guaranteed to fail again. He bought a set of stainless headers and had those put on instead, which is supposed to be the more permanent solution.
