New member on the forum, just became the proud owner of a 2007 2500HD D/A Crew Cab LT2 4x4 with 8800 miles. I've read on some sites about the use of diesel lubricants at each fillup like Stantadyne, AMSOIL, etc. From what I've read the purpose was to provide lubrication that's not provided in the low-sulfur diesel that's in use now, as the older motors were not designed for low-sulfur fuels. My truck has the LMM motor, which I believe was designed with the ULSD diesel in mind. Do I still need to use these lubricants?

 

you will always be better off using quality lubricants anywhere in your truck. Amsoil is about one of the best available. I run my truck 15K miles on it between oil changes and it is guarantedd for 25K.
I think, you are referring to special additives that are recommended for diesel engines, so called surfactants. basically, soaps. They keep engine clean as it needs it because of the diesel fuel.

see this:

A question came up some time ago about using diesel-rated oils to flush out petrol engines. The idea was that because of the higher detergent levels in diesel engine oil, it might be a good cleaner / flusher for a non-diesel engine. Well most of the diesel oil specification oils can be used in old petrol engines for cleaning, but you want to use a low specification oil to ensure that you do not over clean your engine and lose compression for example. Generally speaking, an SAE 15W/40 diesel engine oil for about 500 miles might do the trick.


detergents, like I mentioned. anyhow, you must stick to diesel engine grade oils.

http://www.carbibles.com/engineoil_bible.html