Will a 398.4 citation put my truck out of service?
No. Across our 13 million+ inspection records, 398.4 has resulted in zero out-of-service placements—a 0.0% OOS rate. This code is not OOS-eligible under FMCSR rules.
For context, the all-FMCSR average OOS rate is 31.4%, so this violation sits well below the national baseline for enforcement severity.