The structural stability of mixtures of old and new bituminous binders was studied using three-dimensional turbidimetric titration, where the three dimensions are a visualization of the Hansen solubility parameters showing dispersive, polar, and hydrogen-bonding components. The study was initiated to investigate the possible consequences of mixing old and new binders during asphalt recycling. However, the titration method used is new, and an assessment was needed before evaluation of the structural stability of mixtures of old and new binders could begin. The results showed that three-dimensional titration gives more-detailed information regarding structural stability, compared to one-dimensional Heithaus titration. It was also found that the technique used for automatic detection of precipitation must be further developed. The results regarding mixtures of old and new binders indicated that structural stability is not a limiting factor in asphalt recycling, provided that the old and new binders are compatible.