In 1979, further upgrades were introduced. Engine cooling was improved by switching the locations of the fan and radiator. Higher-strength torsion bars increased ground clearance, and shock absorbers reduced the effects of ground strikes. Armored fuel tanks were added externally on both sides of the rear ramp, freeing up of internal space. The weight of the M113A2 was increased to . Because the added weight affected its freeboard when afloat, it was no longer required to be amphibious. Four-tube smoke grenade launchers were also added. The suffix A2 is used on all variants to denote upgrade to A2 standard.