Gear Question

[fordfrk347]

I had my 4.10's installed by a friend who has done gear swaps for me multiple times before with no issues. This time I had him install an Auburn lsd too. I used the oil that came in my ford axle kit which is synthetic. He did not use friction modifier. When I drive my marauder it runs great and is perfectly quiet until I am almost stopped or just barely rolling. It feels like the gears are binding up or something. Only happens when going straight not when turning. My friend thinks its the auburn chattering but wouldnt that only happen when turning? I'm going to add friction modifier but i have big doubts on that fixing it. Its dead quiet above 5mph. No noise or vibrations. Any help is appreciated!

[FordNut]

Sounds like the gear setup is off. The posi clutches shouldn't chatter when going straight.

[fordfrk347]

That was my thinking but I would have thought there would be noise or vibration as the speeds increased if it was off much. It says on Auburns website to install bolts from an open diff that are a little shorter but it doesnt say why. Guess I will have to take the cover off and look.