I've noticed that the older W250/30s had the Cummins badge on top of the "Power Ram," and the D series had it under the "Ram" In 91, they changed the badging to RamX50 with the Cummins umder it, and added a smaller "Power" on top of it. CLear as mud, right? Glad I could contribute.
The LSD was an option in 92; Mom's has one. She took it in to a shop to get the pinion seal replaced, and the guy put some kind of red oil in it, and it burned up a set of new clutches I had put in 3 mo earlier. Of course, it wasnt HIS fault. No, cant be a mechanic's fault when the fluid HE installs burns up a LSD. Ignorant, inbred, cross-eyed, bucktoothed, average example of a southeast Missourian. God, I cant wait to get outta of this turd pile of Hades' outhouse.
Daniel