rear end pinion leaking??

[melmount]

I put an 08 rear into my 01 truck.
I pulled the drive shaft to grease the slip yoke today. There was gear oil between the pinion and the flange. Let me explain, there a bit of a hollow area for fluid to hold up in. Basically the pinion seal is not leaking. The fluid is somehow getting thru or into the pinion itself and between the flange thats torqued down to the rear. I may have slightly overfilled it (not by much) Never have i seen anything on the ground, nor is the rear end area wet from oil leakage. I dont see how oil is getting between the flange and the pinion itself to get out thru the front. Its not leaking in the ares where the seal will allow it. Its totally dry there.
new to me having oil get between the pinion shaft and the flange??

[melmount]

Can someone tell me the fluid capacity of these rears? its a 10.5 410 posi srw
thx