I am driving home from a meeting yesterday and I notice that my O/D off light is flashing. I drive home approx. 25 miles and the truck still seems to be running and shifting fine. The only time the tranny seems to have any issues is when I am slowing down. Once the speedo hits 25mph while slowing, the truck shifts kinda hard. Upshifting is still smooth and RPMs are still normal. Any suggestions as to where I should go from here?

 

Welcome to the forum!

The obvious answer is to get the transmission codes read to see why the system is telling the O/D light to flash. Since it's the O/D light rather than the Check Engine Light, chances are quite good that a standard scan tool will not be able to access the code responsible for the O/D light. Instead you'll need a professional scan tool that is able to access the transmission system.

Without that information you'll likely be stuck with changing the fluid and filter to see if that "fixes" anything, then swap out transmission speed sensors followed by the Transmission Fluid Temperature (TFT) sensor, and likely still not fix the issue.

-Rod