DHK 8381-209 isn't fit for 8382 Maximus, only fit for 8381 Optimus, 8384 Zombie 8E
If you want to use this part, your car have to update full set parts as below:
8381-121 ------- 8381-108 Gear-18T (2 pcs)/gear-12T (4 pcs)
8381-122 ------- 8381-102 Diff outdrive/pins (dia 2*10mm)
8381-123 ------- 8381-116 Pinion gear outdrive/pins(dia 2*8mm)
8381-124 ------- 8381-112 Assembly of the pinion gear
8381-125 ------- 8381-100 Assembly of diff gear box
8381-126 ------- 8381-101 Diff set
8381-209 ------- 8381-200 Central Diff Gearbox (Complete)
8381-210 ------- 8381-201 Central diff set
8381-737 ------- 8381- 735 A dogbone pin
8381-736 ------- 8381-708 wheel axle (2pcs)