As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
DFW - FLT 598 - DURING TAXI AIRCRAFT FILLED WITH SMOKE ACCOMPANIED BY A DIRTY SOCK SMELL. AIRCRAFT TAXIED TO GATE WITH NO FURTHER INCIDENT. FOUND HYDRAULIC LEAK AT LEFT ENGINE HYDRAULIC SYSTEM. SYSTEM GROUND CHECKED NORMAL OPERATION. (M)