<< How about Mobil 1 Synthetic Gear Lube LS 75W-140 or Mobil 1 Synthetic Gear Lube LS 75W-90?? >> Honestly Skip, I have ZERO clue. And above all, I wouldn't take a chance with a Customer's car nor my own unless I DID have some concrete info. The Redline Line products I HAVE read & heard [Skip Kelsey] enough to trust/try it. Me