yo Bob,
Fill with Motorcraft MERCON® ATF XT-2-QDX or MERCON® equivalent fluid to correct level
Remove the fill plug from the rear transfer case (7A195). Fluid level should be just below the fill plug. TWO Quart Capacity
Transfer Case Borg Warner 1356
Item Part Number Description
1 7E440 4WD Indicator Switch
2 7B106 Shift Lever
3 7B214 Case Yoke
4 7061 Output Shaft
5 87675-S Fill Plug for PTO Use
(F-350 Only)
6 7017 Input Shaft
7 87675-S Fill/Drain Plug
1356 Fluid Drain & Fill Plug Size; "...It's a 10mm square hole. People strip out the plugs when they use a 3/8" extension which is slightly smaller than 10mm plus extensions do not have sharp edges/corners which makes it worse..."
Source: by Dustin S