Re: friction modifier in differential?
Even Amsoil says try without it and if you have chattering to add it then. For what it's worth I have never had to add any to any of my newer trucks (04 up) but I have a few vans with the LS that will rattle your teeth without it. Seems to be a case by case basis.
It feels like someone just had forced buttsecks with my eyes.
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