Tom,
You're pretty safe with any gear
oil that states that it is for use in limited slip diff. Your carrier is basically the same as a Dana 44.
I have not found it necessary to utilize special additives in either Jag or Dana applications. I have not experienced chatter or unusual wear.
I will be frank, I don't like Pennzoil in an engine at all. It is parafin based and the sludge is incredible. Don't know if the diff.
oil is the same or not.
Personnally, I like Kendall products. Frankly though, I've used NAPA diff.
oil and never had any problems, so go figure.
You can make it unnecessarily complicated by listening to all of the hype. If you want to feel more secure, buy what the Jag dealer in your area sells or recommends.
Al