The US E36 M3 (S50 in 1995, S52 in 1996-99) came with the ZF 320 (S5D 320Z) five-speed — a stout, well-regarded box that is NOT a known weak point.
There was no factory US E36 M3 manual famous for "sticking in a gear", and the SMG/sequential dramas belong to the later E46 M3, not this car.
Treat a healthy E36 M3 manual as reliable. The wear items are:
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