Components of road runoff have been correlated to adverse health outcomes in fish and aquatic invertebrates residing in urban bodies of water. Recently, a transformation product of the antioxidant chemical added to car tires, N-(1,3-Dimethylbutyl)-N’-phenyl-p-phenylenediamine (6PPD-quinone, 6PPD-q), was found to induce urban stormwater mortality syndrome in salmonids. Exposure to 6PPD-q has the potential to increase the sensitivity of salmonids to other co-occurring contaminants commonly detected in surface waters, such as the polycyclic aromatic hydrocarbon 9,10-Anthraquinone (AQ). Liquid chromatography mass spectrometry-based metabolomics and transcriptomics were utilized to elucidate sublethal toxicity and mechanisms of action of road runoff pollutants among Oncorhynchus. mykiss, O. kisutch, and O. tshawytscha, were chosen to represent a range of sensitivities to 6PPD-q and fill current data gaps in the literature. Juvenile fish were exposed to established sublethal concentrations of 6PPD-q and AQ, both separately and in combination, over a five-day period. Non-targeted MS-based metabolomics analysis and RNA-sequencing were conducted on liver samples. Using in-house and open-source spectral libraries, 260 metabolites were confidently annotated in liver tissues. More differentially expressed genes were identified in coho exposed to 6PPD-q compared to rainbow trout and chinook. This study provides mechanistic insights into 6PPD-q and AQ toxicity in salmonids, highlighting oxidative stress, mitochondrial dysfunction, and impaired detoxification as key drivers of sublethal effects. Furthermore, the observed increase in metabolic activity in AQ and co-exposure treatments suggests that AQ may influence the biological response to 6PPD-q, potentially by inducing antioxidant defenses and xenobiotic metabolism. In the co-exposure scenario, this may contribute to an antagonistic interaction, attenuating some of the toxic effects of 6PPD-q, though this should not be interpreted as a beneficial or protective effect of AQ.