This paper presents evidence that tongue-body position is always specified in the phonological representation of coronals, even where it is non-contrastive. Tongue-body position is needed to account for the typology of interactions between coronal consonants and adjacent vowels. For example, coronals only condition vowel fronting if they are produced with a front tongue body (usually anterior coronals), and only coronals produced with a back tongue body (usually retroflexes) condition vowel retraction. However, coronals do not have a fixed tongue-body position. Tongue-body position is affected by the position of the tongue tip/blade, because these articulators are physically connected, so each type of coronal has a preferred tongue-body position that facilitates the production of the coronal constriction. These preferences can be overridden, however, e.g. due to assimilation to a vowel. Optimality-theoretic feature co-occurrence constraints provide a good account of this type of dependency between articulators.