This article investigates the impact of the type of carrier medium, varying particle proportions, types of particles, and additive proportions on the sedimentation ratio as well as off-state viscosity of the synthesized MR fluid samples. The MR fluid sample comprising silicon oil as a carrier fluid, carbonyl iron particle with 6 mm average particle size (APS), 24% proportion of Fe particles by volume, and 2% ethylene glycol monostearate exhibits the best sedimentation stability. The MR fluid sample containing silicon oil as a carrier fluid, the electrolytic iron particle with 32 mm APS, 16% proportion of Fe particles by volume, and 1.5% ethylene glycol monostearate exhibits the best (lowest) value for the off-state viscosity. The value of off-state viscosity for all 18 prepared MR samples ranges from 0.284 to 0.612 Pas at a shear rate of 1000 s−1 & this rheological property exhibits a decline with a rise in shear rate. The optimal results obtained through the design of experiment (DoE) methodology have been validated using a confirmation experiment.