Function: Enables torque multiplication in 1st-3rd gears via compound planetary gearset and clutch packs.

Key Components:

• Front Planetary Carrier: Hardened steel gears with needle bearings.

• Low/Reverse Clutch Drum: Houses 4-6 friction plates (OEM code 52129196AB).

• One-Way Clutch (OWC): Sprag-type design for seamless gear transitions.

Failure Modes:

• OWC Roller Jamming: Causes harsh 1-2 shifts (P0720 output speed sensor correlation).

• Planetary Bearing Wear: Leads to gear whine (check endplay <0.25mm).

• Clutch Drum Scoring: Metal debris locks plates (no movement in Drive/Reverse).