PRODUCTION TRUCK #213 WAS BEING LOADED WITH SURFACE MATERIAL BY THE #61 PRODUCTION SHOVEL. WHEN THE LAST BUCKET WAS PLACED IN THE TRUCK, THE DRIVER REPORTS HE EXPERIENCED A NECK STRAIN. THE ONLY NOTICABLE MOVEMENT WAS A SETTLING OF THE RIGHT SIDE SUSPENSION(S) AS THE LOAD SETTLE. THE TRUCK WAS REMOVED FROM SERVICE FOR DIAGNOSIS AND REPAIR AS NEEDED.