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1973 K20 - 350/350/205
Quote: The NP 203 is an aluminum, chain driven, full time transfer case. It is weaker than the "bulletproof" NP 205.
Quote: One way to tell them apart is to look at the hubs on the front axle. manual locking hubs indicate a truck with the NP 205 and a man. tranny. Automatic hubs with "4x4" indicate a truck with a NP 203 and a TH350/400 tranny.
'79 GMC shortbed 454 th400 14 bolt FF NP205 Dana 60