I just swapped out the OEM differential cover for one from Trick Flow. The directions said to fill it to the fill hole on the cover. That only took 2 quarts though. My owners manual says 2.6L which is a little over 2.7 quarts. The dealer also said it should be around 2.5 to 3 quarts. I was able to get about 2.8 quarts in using the original fill plug. Should I leave it as is? If not, what would you recommend doing?