Brother DCP-L8400CDN Service Manual page 361

(11) Release the Hook and remove the Gear 33 from the T2 frame L unit.
Gear 33
<Left side>
Hook
(12) Remove the Extension spring from the Spring hook.
(13) Release the Hook and remove the Gear 46/55 from the T2 frame L unit.
T2 frame L unit
Hook
<Left side>
Extension spring
Fig. 3-291
Gear 46/55
Spring hook
Fig. 3-292
3-197
T2 frame L unit
Confidential