will 387.301A put my truck out of service?
No — almost certainly not. Across all 3,309 all-time citations for 387.301A in our inspection records, only 3 vehicles were placed out of service, producing an OOS rate of just 0.1%. To put that in perspective, the average OOS rate across all FMCSR codes is 31.4% — meaning 387.301A sits roughly 300 times below the national average. This is an administrative/documentation violation. Inspectors use OOS authority here only in the rarest circumstances. You will almost always be allowed to continue driving after the citation is written.