They don’t send owners letters about TSBs. Unless you have a dealer, or tech that studies new TSBs every day (remember, they have three other vehicle lines they usually deal with also), they won’t know about it until someone brings in a vehicle with symptoms. Then they search the database for TSBs that might have to do with the issue the customer describes. You might get a sharp tech that can say, “oh yeah, I remember seeing a TSB regarding that issue”, but you gotta realize there are thousands of them that cover issues with ram, jeep, dodge, and chrysler.