Organosilane coatings are applied to metal substrates for corrosion protection and promotion of adhesion to polymeric primer coatings. The metal oxide – organosilane interface is crucial to the adhesion performance of the entire coating system. Nevertheless, interfacial molecular information, required to point out which chemical binding interactions are accountable for strong adhesion, is often missing. Surface sensitive chemical analysis techniques are required to probe the ultrathin interface, but demand a profound strategy to access the industrial interface which is usually buried under a micrometers thick coating. In this work, state- of-the-art time- of-flight secondary ion mass spectrometry (ToF-SIMS) and X-ray photoelectron spectroscopy (XPS) instruments will be employed complementarily to study the metal oxide – organosilane interface. These techniques present the advantage of being surface sensitive analysis methods (surface sensitivity of the order of 1 to 10 nm) capable of extracting molecular information, making them suitable for investigation of ultrathin interfacial layers. Novel technique hard X- ray photoelectron spectroscopy (HAXPES) allowing access to previously inaccessible deep core levels will enable to probe the hybrid interface buried under thick coatings, as this provides a better representation of industrial coating systems. This work will bring new insights on the technique, exploring its advantages and limitations. Brand new information is provided about interpretation of HAXPES data towards interfacial bonding in metal oxide/silane interfaces. Important industrial process parameters such as curing temperature are evaluated in view of adhesion performance.