M113 armored personnel carrier variants were created for a variety of uses such as transporting infantry and nuclear missiles. The M113 armored personnel carrier has become one of the most prolific armored vehicles of the second half of the 20th century, and is still used by various armies around the world.

Military operators

Afghanistan In 2005, Afghanistan received 15 second-hand M577A2 command and control vehicles from the United States.

Argentina

In 1967, the Argentine Army received from USA 250 M113A1 APC, 10 M577A1 command and control vehicles and 12 M548A1 cargo carriers. In 1992, they received from USA 200 M113A2 APC, 25 M106A1 mortar carrier, 10 M577A1 command and control vehicles and 16 M548A1 cargo carriers. Some variants are modified by the Army's Comando de Arsenales.

M106A2 – M106A1 mortar carrier modified with a 120mm FM mortar. M113 Defensa Aerea – M113 APC with a 20 mm Oerlikon GAI-BO1 cannon. M113 Sanitario – M113 APC modified to serve as an armoured ambulance. M113 Recuperador – M113 APC modified to serve as an armoured recovery vehicle M113 Comunicaciones – M113 APC modified to serve as a communications vehicles M548A2 – M548A1 cargo carriers modernizated to A2 version. M113A2 RASIT – M113A2 APC fitted with a RASIT radar to serve as reconnaissance vehicle. M113A2 w/ 20 mm turret – M113A2 APC fitted with a CITEFA 20 mm turret.

Australia

Some Australian AFVs have the suffix "AS" (the NATO code for Australia), often appended by a model number.

Generally speaking, Australian models are modified from the original models, in the case of the M113A1 series this included the AN/VIC-1 communications harness, large dust filters for the passenger compartment ventilation blower, heavy steel track manufactured by ADI, provision for 600 kg of belly armor, the Cadillac-Gage T-50 turret mounting twin .30 Brownings (early service) or a .30/.50 Brownings machine guns for APC/LRV versions, a traverse bar to prevent the crew commander traversing the turret to the rear over the troop compartment roof hatch with the guns depressed low. For some reason, besides the M577A1 command vehicle, all of versions of the M113A1 had the passenger compartment heaters removed. In the late 1980s, the fleet was issued with German BM8005 image intensifying night vision driving periscopes, which, with the aid of an adaptor, could be fitted to replace the driver's central periscope for night driving. In the early 90s, the fleet was issued with VINSON family cipher equipment, typically a single KY-57 per vehicle. This allowed the command net to be enciphered, but the admin net would normally work en clair. M113A1 Fire Support Vehicle (FSV) – Full designation Carrier, Fire Support, Full Track M113A1 (FS) Saladin TurretJohn Myszka, Military Briefs, vol 1, Australian Fire Support Vehicles, 1999 Mouse House Enterprises, . was a variant fitted with the turret from the Alvis Saladin armored car. The FSV was introduced into Australian Army units in the mid-1960s following the withdrawal of the Saladins and was armed with a 76 mm gun, a .30 caliber coaxial machine gun and a .30 caliber machine gun mounted on the roof of the vehicle's turret. The M113 was an interim vehicle and was replaced by the M113 Medium Reconnaissance Vehicle in the late 1970s. It was commonly referred to by Royal Australian Armoured Corps crews as the "Beast". M113A1 FSV is still under service by Philippine Army. M113A1 Fitter – Armored recovery vehicle with HIAB (Hydrauliska Industri AB) crane mounted on the left side of the hull roof along with a counter weight on the opposite side of the roof. The vehicle can be armed with either the L3A4 machine gun, M60 machine gun or a M2HB .50cal machine gun. M113A1 Light Reconnaissance Vehicle/APC – A standard M113A1 with a Cadillac Gage T50 turret as used on the V100/V150 series of armored cars, mounting two Browning machine guns, a .30 caliber and a M2 .50 caliber machine gun. While the standard armored personnel carrier version in Australian service is also fitted with the T50 turret, it initially carried only twin .30 caliber machine guns. In later service, the LRV and APC versions both carried the 30/50 combination and the only difference between them was roles. LRVs, which carried a crew of 2 or 3 (crew commander, driver and sometimes operator/observer), were used in the sabre (recon) troops of the Cavalry regiment and the recon troop of the Armoured regiment. APCs carried a crew of 2 plus several dismounts, either infantry, assault troops, engineers or other troops. In practise, an LRV was also perfectly capable of carrying troops, though in perhaps somewhat more cramped conditions as LRVs often carried additional stores and ammunition and had seats removed and replaced with storage lockers. For a short period of time in Vietnam, the Aircraft Armaments Incorporated Model 74C Cupola/Command Station was used, but it was quickly replaced by the T50.Michael K. Cecil, Australian Military Equipment Profiles, vol 4, The M113 & M113A1 Armoured Personnel Carriers in Australian Service 1962–1972, 1994 Australian Military Equipment Profiles, . Also used by the New Zealand Army until the M113 was replaced in 2005. The T50 turret was initially fitted with an optical sight, however in later years this was removed and the guns were solely aimed using ranging bursts of 6–10 rounds (2 tracer). The diesel burning heater is removed from the M113A1 – though numerous diggers note that this is not the case with the Australian Army's M577s (command post vehicles). M113A1 Medium Reconnaissance Vehicle (MRV) – Full designation Carrier, Fire Support, Full Track M113A1 (FS) Scorpion Turret was an Australian variant similar to the M113 FSV, but using the turret from the FV101 Scorpion light tank, instead of the older turret of the Saladin armoured car, that the FSV had previously used. This turret was equipped with an Image Intensifier sight for the main armament. This II sight was the first effective passive night sight fitted to an Australian AFV, giving the MRVs a night fighting capability exceeding the Leopard AS1 and all other Australian AFVs of the period. Whilst fully amphibious, the MRV was also fitted with a light sheet-metal foam-filled trim vane and side pods. These pods and the trim vane were intended to provide additional flotation and stability on the water; they provided virtually no additional armour protection. Other changes included a modified driver's hatch which pivoted toward the centre-line of the vehicle instead of opening to the rear of the driver's hatch; this feature preventing the open driver's hatch being caught on the traversing turret, as well as the fitting of the British "boiling vessel", an electric vessel for boiling water and heating rations. As indicated by the designation change, the MRVs were roled as reconnaissance vehicles and issued to the Cavalry (medium reconnaissance) regiments with each troop equipped with 3 LRV and 2 MRV; whereas the FSVs were originally issued to APC squadrons and used to provide infantry fire support. The MRV replaced the FSV in Australian service. M113A1 MRV served in the Australian Army until 1996. M113AS3 – significantly upgraded M113A1 with new engine, transmission, steering, suspension, brakes and hull protection. M113AS4 – upgraded to the same standard as the AS3, lengthened to fit an additional road wheel station and fitted with a new Tenix Defence designed electronically driven "one man turret" with 12.7mm heavy machine gun and sight.

Brazil M113B – Basic M113 modified by Motopeças, of São Paulo. The original Chrysler 75M petrol engine was changed to one Mercedes-Benz OM352A diesel engine, with 180 hp. Transmission and other parts are changed too. M113BR – Modernization of M113B, made by BAE Systems and the Brazilian Army's Parque Regional de Manutenção/5 (Regional Maintenance Park nº5), in Curitiba. Is a version of M113A2 Mk.1 modernization pack, of BAe Systems, fitted with a Detroit Diesel 6V53T engine, with 265 hp, Allison TX100-1A cross-drive transmission, Harris FALCON III radios and Thales SOTAS intercom. M113-T – Proposed modernization of M113B by Tractto, Medianeira Mecânica and UFSM. Fitted with a MWM engine. M577A2 – Command and control version of M113A2, donated by the US. 34 delivered in September 2016.

Belgium BMF from Belgium has built the M113A1 with some modifications (using the suspension of the M113A2, NBC protection system etc.) under license as the M113A1-B, The Belgian army received 525 vehicles from 1982. M113A1-B-ATK – Basic APC version with M2HB .50cal machine gun. This type is no longer used and most have been modified into new versions. M113A1-B-Amb – Ambulance with room for 4 litters. This type is unarmed but is fitted with six 76mm smoke grenade launchers. M113A1-B-CP – Command post vehicle that retains the low roofline of the basic version. M113A1-B-ENG – Squad vehicle for combat engineers. Some of the 113 delivered are fitted with an hydraulic dozerblade. M113A1-B-TRG – Driver trainer. M113A1-B-MIL – Tank hunter with pintle-mounted MILAN and two 71mm Lyran mortars. All 56 vehicles have been modified into artillery FO vehicles. M113A1-B-Mor – The original version was used to carry the M30 4.2" mortar, but all 35 vehicles have been upgraded to tow the Thompson-Brandt MO-120-RT 120 mm mortar. M113A1-B-MT – Maintenance vehicle with folding work table on the right rear. M113A1-B-MTC – Maintenance vehicle with hydraulic HIAB crane. Similar to the M579. M113A1-B-Rec – recovery vehicle with a heavy internal winch. Similar to M806. M113A1-B-SCB – Carrier vehicle for mast-mounted battlefield surveillance (Surveillance de Champ de Bataille) radar EL/M-2130A. M113A1-B-TACP – Modified command post vehicle for dedicated TACP missions. M113A1-B-VW – Former MILAN carrier that is now used by artillery forward observers. It retains the .50cal machine gun on the 3rd cupola behind the driver, but the commander's cupola has the MILAN post replaced by a portable laser range finder MLR-N61. AIFV – A development of the M113A1 APC, upgraded with an enclosed turret and firing ports.

Canada Models in service:

Under the Armoured Personnel Carrier Life Extension (APCLE) program otherwise known as M113LE Project, which was started after the 1994 White Paper on Defence, it was originally planned that 341 Canadian M113A2 series vehicles were to be upgraded under the contract issued in 2000: 183 were to be stretched by 50 cm and fitted with 6 road wheels and a one-piece rubber Band Track (which is prone to slipping off the running gear during high speed turns) as part of the MTVL (Mobile Tactical Vehicle Light) series upgrade. The remaining 158 vehicles were to be upgraded to M113A3 standards, retaining 5 road wheels. An optional additional order of 61 air defence vehicles either to the MTVL or M113A3 standard of upgrades for both existing M113A2 ADATS and to convert additional APCs for use as ADATS platforms was also considered. The program underwent three reductions including scrapping the optional ADATS update order and it reduced the total number of vehicles down to 254 vehicles, with just 112 MTVL standard and 142 M113A3 standard being produced starting in 2002.