8-3/4 Noise After Rebuild..What's Normal??

pastortom1 said

When you guys state "friction modifier", are you talking about the whale oil additive?.............and should I add it now, or drive the thing for a break-in, then drain and add or change the oil..........and what about the royal purple for the oil after some miles............I've heard this oil is the best from a lot of pro's..........BUT, need input from you guys...........:book:

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Pastortom, you need to get some of the limited slip/posi additive in that rear "ASAP" and both GMC and Mopar dealers carry it. You haven't mentioned how many miles you've got on the gears (I realize it's not much) but I'd give them at least 1000 miles to quiet down. Keep the builder in the loop so that if someting does go wrong they're still on the hook. Personally I've heard gears that had a slight whine like you can't hear the whine over the car radio and last for years.

terry