Question for those of you who have the stock 10 bolt with an aftermarket differential cover such as Mac or Summit that has the bearing supports. Do you fill the differential to the bottom of the fill hole located in the cover? The reason I ask is that before using this cover you would fill to the bottom of the hole located on the right side of the differential which is a little lower than those located in an aftermarket cover. I use the Torsen unit with a Mac cover and have just put 2 qts of Lucas Synthetic 75-90w lube in and I can't feel the lube when I stick my finger in for reference. Finally getting things back together after getting my PBR rear discs bolted up and want to fill the differential accordingly. Thanks.

 

Fill only to the factory fill plug; otherwise, all that extra fluid just reaches the level of the carrier bearings and just goes into the tubes, and leaks out the axle seals.

Most of the aftermarket covers hold a bit more fluid than factory covers. Expect 2½ - 3 quarts or so.

 

I have the TA cover and directions state remove the factory plug and fill until it runs out the factory hole.

 

Thanks for the replies, I will pull the factory plug and see where I am at with the level.