So i just test drove my car around about 10 miles. Everything is good, except i have gear noise during accelration. I dont hear anything until i get around 40+mph.

This is a used set. i guessed the preload on the pinion. pattern came out good with a little shimming around with my carrier. I know gear oise is normal but just wanted to check with others. so thanks in advance.

Could it be either of these?

1.) Not enough preload on pinion because i guessed and didnt want to over shoot.
2.) more gear oil, i put in 2 liters, but its not to the fill hole yet.