IRS fluid

[Packer fan]

Hi,
I just drained the fluid that was in the IRS from the factory because I didn’t know how much or what was in there. I then put royal purple 75 w 90 in it. I was expecting it to start to come out the fill hole when it was full. I read that it was suppose to take 1.6 quarts plus 4oz. After putting the entire 2 quarts in none was coming back out the fill hole. Should I drain some out? Or put more in?

Thanks

[Railroad]

The case has to be sitting like it will be while in the car on level ground.

[Packer fan]

The case is mounted in the car and it is level in my garage. I believe that it is right at the edge if the hole. I guess it will be ok. I just wanted to make sure that I wasn’t suppose to go by volume (1.6 qt.), but to the full mark (fill hole). I will probably pull the top plug to let any excess come out when on the street that might be a little more level.