So did you figure out what a 3rd member is? In a 3rd member differential design, the entire differential assembly is attached to a removable section of the differential housing. You can remove said 3rd member, work on it on a bench including seething the pinion backlash then once set up install the entire assembly in the main diff housing.

From what ive been told its a very common setup in arge truck axles (semi's), etc.

Off Roader
98 Montero with the Winter Package
89 Montero minty clean and reserved for overlanding trips or Cars and Coffee events
96SR (3.15:1 xcase, 35's) gone to the rust gods
96SR Build Up Thread
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