Redline Gear Oil failed 2 basic gear oil tests, foaming and viscosity, according to this white paper http://www.amsoil.com/lit/g2457.pdf .
Does Red Line offer a warranty? I searched "warranty" on their website and found nothing.
This is also not confidence inspiring.
"Q: Will using Red Line products void my vehicle's factory warranty?
Using the appropriate Red Line product shouldn't invalidate your vehicle's warranty and question the mechanic or service manager that says so."