The aim of this thesis is to explore and improve the accuracyofweight estimation in vehicles with air suspension. The main focushasbeen to understand the hysteresis and characteristics ofdifferentsuspension types used in Scania NCG trucks. The thesis hasled toinsights into the attributes affecting hysteresis and theaccuracy ofweight estimation. As a proof of concept a softwareimplementationhas been developed from the knowledge derived troughout the thesisto account for hysteresis. The result of this work hasproven it tobe possible to increase the accuracy and reduce the errorto lessthan half compared to today's method.