Why won't the left clutch engage properly on my Case 455C dozer?

[Harvey Esteban]

I'm having a steering clutch issue on my Case 455C dozer. The left brake applies immediately without the clutch disengaging first, while the right side works normally, with the clutch engaging before the brake. I've already removed and checked the transmission control valve, and the clutch spool doesn't appear to be stuck. Could the brake valve assembly be causing this issue, or is there something else I should inspect?