[Fat Charlie]

Used to and Lots of are... old.

Yes, the lube oil got filtered constantly, but it was formulated to stick together to maintain a film under harsh conditions, not to get spritzed into a fine mist by the injectors. That alone should give one pause.

I'm not up on diesels, as such: I'm a parts guy, and I hate diesels because they're difficult (not efficient on my end). Older diesels could run on pure ATF, straight WMO, whatever the hell you could fit in the tank. Everything runs tighter nowadays, and newer ones (06+?) are also less forgiving because of emissions rules. I've seen clogged injectors from mixing WMO with the fuel.

In the newer, more highly strung diesels, I'm not a big fan of additives. There's a place for them, but use a light brush.