light weight, leading to fuel savings
A 22.5-inch forged truck rim, for example, weighs only  21.8 kilograms, compared with 40 kg for a steel rim The use of forged rims can result in fuel savings of 5% to 8%

Safety
forged rims offer much better heat dissipation, which is especially important for long-distance trucks. A lower rim temperature results in less tire fatigue and better braking