Well, it only took about 20 min to convince DC they screwed up and walk away with all the parts to "re" service both axels with Mopar 75W140 synthetic. We both agreed that we learned something: Me- don't trust DC Them- 2500 diesels use different oil.

The parts manager checked their computer, spec books, oil charts and went to the shop to ask the mechanic. After admitting it should be 140, he said their shop used 75W90 in everything.

 

Let me see, pay 4 times(or more) for Synth, no guareentee that LS will work. Need to change at 20k anyway, due to clutch pak wear. No real issue with the DINO lube.
Is DC getting kickbacks? Sounds good on paper, but your LS may not work!
Why bother?

 

Here's how I see it (like you care right?). I take it to them for my free oil changes. The man say's "You are due for the rear-end service." I say cool, do it. He does it. I pull my 13k pull/toy box type trailer 320 miles (one way) up two large grades and many other small ones to the June Lake Loop area in 100+ (as high as 120) degree heat. I do this at about 80mph and make the round trip every week. If she blows, they fix it. I told them I tow. They've seen the trailer. When I'm out of warranty I'll probably think differently. I've got 100k to find out if their service intervals are enough.