Thanks....I'm gonna try the teflon tape on the fill plug. I think the diff was over initially  filled based on how much gear 
oil drained when I removed the plug so that may be part of the issue. I emailed KMS to ask what 
oil level they recommended for their diff. Should it be to the fill hole or slightly lower. I've been told both. 
Also asked them what gear 
oil they recommend and if friction modifier was needed on the TrueTrac diff ( think that's what the T.T. stands for) ... again...been told yes and no. 
Hopefully get it figured out a sealed up tight!!!!