In February 1943, US Sixth Army decided that the battalion was obsolete, and removed the unit's 800 mules, as well as its commander, who was transferred to the 1st Cavalry Division.

Late in the year, the order came through for the battalion to prepare to take part in the landings in Lingayen Gulf, which were to form the invasion of Luzon.

Elements of the battalion were sent to Santiago Island to secure the entrance to the Gulf and prevent the enemy outflanking the landing area.

[6] Sixth Army Intelligence indicated that the Japanese were holding a large number of American POWs in Cabanatuan, 60 miles north of Manila.

General Walter Krueger, Sixth Army commander, ordered 6th Rangers to "bring the prisoners out alive".

Alamo Scouts and Filipino guerrillas accompanied the 6th Ranger force, and provided reconnaissance and flank protection.

[8] For the remainder of the Luzon campaign, the 6th Rangers performed a variety of small-scale missions, including long-range reconnaissance patrols, mopping up bypassed pockets of Japanese resistance, and serving as a headquarters guard for the Sixth Army.

On 23 June, they seized an airfield near the town of Aparri to prepare for the arrival of Task Force Gypsy, comprising 11th Airborne Division paratroopers and glider troops.