How much whine is normal for a new sure grip rear end?

There are some ratio gears that over 4.88 can make some noise, but only at higher cruise speeds, most gears shouldn't make a sound ever.

The china copy cat stuff can be a issue with set up, and i believe they make noise mostly because they don't set up right and you have to read them and adjust to make them set up right, which is why i don't like getting involved with china stuff, when you set the pin height and find out it's afu and way off and now 3 hours turns to 6... Some shops i think get frustrated and thats it and get it the F outta here..

I have corrected gears that people came in with them singing from 10 to 70mph on the up and down side (had 3 like that , how they lived with it for so long is beyond me), had one jeep where they drove it like that for a year and a half, and i have got them quiet, if the shop knows what they need to look for and adjust for they can straighten it out, especially if this is new.

There are cases when they are driven hard and hammer the gears to a gouging effect on hard use and they create a high spot for the gears to run on when adjusted which can lead to other issues, re-setting gears that have been run long are a MF'er to read and set so don't wait.

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