Are you using M/T ET Street bias plys or ET Street Radails and what size? Also what pressure are you using and what width rims are they on now? I bought a used set(2/3 rds. worn out) of 12.50x30x15 ET Sreet bias plys last year from another memember on here that where pretty old, they wouldn't hold air when mounted tubeless I soaped the inside and ran them tubeless for the rest of the year, 1.43 60 ft. times on them