Copy this new line to TLAD or TBoGT default.ide on Grenade Launcher line.

TLAD
w_e1_glauncher,		w_e1_glauncher,		gun@shotgun,	              1,	100,	0

TBoGT
w_e2_glauncher,		w_e2_glauncher,		gun@shotgun,	              1,	100,	0

After that, go to TLAD or TBoGT WeaponInfo.xml and copy the new line below:

TLAD
	<!-- GRENADE LAUNCHER -->
	<weapon type="EPISODIC_1">
		<data slot="HEAVY" firetype="PROJECTILE" damagetype="EXPLOSIVE" group="GRENADE" targetrange="30.0" weaponrange="32" clipsize="4" ammomax="12" timebetweenshots="800">
			<damage networkplayermod="2.0" networkpedmod="1.0"/>
			<reload time="2066" fasttime="2066" crouchtime="2066"/>

			<aiming accuracy="1.0">
				<offset 				x="0.15" y="1.0" z="0.53"/>
				<crouchedoffset x="0.12" y="1.0" z="0.05"/>
				<reticule standing="1.0" ducked="1.0" scale="0.0"/>
				<ordnanceoffset pitch="0.1"/>
			</aiming>

			<pickup regentime="600000" ammoonstreet="3"/>

			<controller>
				<rumble duration="100" intensity="0.8"/>
			</controller>

			<flags>
				<flag>GUN</flag>
				<flag>HEAVY</flag>
				<flag>CAN_FREE_AIM</flag>
				<flag>ANIM_RELOAD</flag>
				<flag>ANIM_CROUCH_FIRE</flag>
				<!--<flag>CREATE_VISIBLE_ORDNANCE</flag>-->
				<flag>2HANDED</flag>
				<flag>HEAVY_WEAPON_USES_RIFLE_ANIMS</flag>
			</flags>

			<projectile>
				<typetocreate type="EPISODIC_5"/>
				<offset 	 x="0.55" y="0.0" z="0.08"/>
				<rotoffset x="0.0"	y="0.0" z="0.0"/>
			</projectile>
		</data>

		<assets model="w_e1_glauncher">
			<anim group="gun@shotgun"/>

			<effects>
				<muzzle fx="muz_grenade_launcher"/>
				<shell fx="weap_ejected_shotgun"/>
			</effects>
		</assets>
	</weapon>

	<!-- GRENADE for GRENADE LAUNCHER (not usable as a thrown weapon on its own) -->
	<weapon type="EPISODIC_5">
		<data slot="THROWN" firetype="PROJECTILE" damagetype="EXPLOSIVE" group="GRENADE" targetrange="1000.0" clipsize="1" stattype="EPISODIC_1">
			<damage networkplayermod="2.0" networkpedmod="1.0"/>

			<projectile type="IMPACT">
				<explosion type="EPISODIC_1"/>
				<physics force="160.0"/>
			</projectile>
		</data>

		<assets model="w_e1_grenade">
			<effects>
				<trail fx="weap_pipe_bomb_trail"/>
			</effects>
		</assets>
	</weapon>

TBoGT
	<!-- GRENADE LAUNCHER -->
	<weapon type="EPISODIC_1">
		<data slot="HEAVY" firetype="PROJECTILE" damagetype="EXPLOSIVE" group="GRENADE" targetrange="30.0" weaponrange="32" clipsize="4" ammomax="12" timebetweenshots="800">
			<damage networkplayermod="2.0" networkpedmod="1.0"/>
			<reload time="2066" fasttime="2066" crouchtime="2066"/>

			<aiming accuracy="1.0">
				<offset 				x="0.15" y="1.0" z="0.53"/>
				<crouchedoffset x="0.12" y="1.0" z="0.05"/>
				<reticule standing="1.0" ducked="1.0" scale="0.0"/>
				<ordnanceoffset pitch="0.1"/>
			</aiming>

			<pickup regentime="600000" ammoonstreet="3"/>

			<controller>
				<rumble duration="100" intensity="0.8"/>
			</controller>

			<flags>
				<flag>GUN</flag>
				<flag>HEAVY</flag>
				<flag>CAN_FREE_AIM</flag>
				<flag>ANIM_RELOAD</flag>
				<flag>ANIM_CROUCH_FIRE</flag>
				<!--<flag>CREATE_VISIBLE_ORDNANCE</flag>-->
				<flag>2HANDED</flag>
				<flag>HEAVY_WEAPON_USES_RIFLE_ANIMS</flag>
			</flags>

			<projectile>
				<typetocreate type="EPISODIC_5"/>
				<offset 	 x="0.55" y="0.0" z="0.08"/>
				<rotoffset x="0.0"	y="0.0" z="0.0"/>
			</projectile>
		</data>

		<assets model="w_e2_glauncher">
			<anim group="gun@shotgun"/>

			<effects>
				<!--	<muzzle fx="muz_grenade_launcher"/> -->
				<shell fx="weap_ejected_shotgun"/>
			</effects>
		</assets>
	</weapon>

	<!-- GRENADE for GRENADE LAUNCHER (not usable as a thrown weapon on its own) -->
	<weapon type="EPISODIC_5">
		<data slot="THROWN" firetype="PROJECTILE" damagetype="EXPLOSIVE" group="GRENADE" targetrange="1000.0" clipsize="1" stattype="EPISODIC_1">
			<damage networkplayermod="2.0" networkpedmod="1.0"/>

			<projectile type="IMPACT">
				<explosion type="EPISODIC_1"/>
				<physics force="160.0"/>
			</projectile>
		</data>

		<assets model="w_e2_grenade">
			<effects>
				<trail fx="weap_pipe_bomb_trail"/>
			</effects>
		</assets>
	</weapon>