After recall 24S37 was performed on my Ford F-150 to address potential sudden downshifting to first gear, my truck began experiencing serious transmission issues that had never occurred prior. The recall required PCM reprogramming, and immediately afterward, the vehicle started hard shifting and unexpectedly downshifting at highway speeds (one example 5th to 3rd gear and also while passing or decelerating). This was alarming and unsafe. Before this recall, the transmission operated perfectly with no symptoms, warning lights, or signs of malfunction. I returned the truck to the Ford dealership that performed the recall. Their road test confirmed the issue, and they diagnosed it as damage to the overdrive clutch. However, they stated the damage was likely present before the recall work’despite no prior symptoms’and recommended full transmission replacement at a cost of nearly $10,000, which I declined. The issue clearly began immediately after Fords recall remedy and fits the exact risk the recall was supposed to prevent. The vehicle is available for inspection. I believe the recall work either caused or triggered the failure and that Ford should be held accountable.