Abstract: A radial medium radial truck (RMT) tire has belt or breaker plies which are reinforced by organic reinforcement cords or filaments. In the preferred embodiment, organic multifilaments are used in the top belt or breaker plies which have the following characteristics: at least a gauge of 420×2 dTex to about 3300×3 dTex, a tenacity of about 35 cN/Tex to about 200 cN/Tex, an initial modulus of at least 30 g/denier (250 cN/Tex) and a shrinkage of about 0.1-10 %. When an organic polymer reinforcement is used in the top belt or breaker in the belt package of a tire, scrapping of tires during a retreading operation because of corrosion is greatly reduced. In addition, acceptance for retreadability is increased because of reduced top belt or breaker damage, allowing for easier preparation for the retreading. Moreover, the invention relates to an improved construction to reduce defects known as blows.