My 2009 downshifts hard between 2nd and 1rst gear. Real distinct when stopping at a stop sign. I have 81,000 on it. I looked at older forum's and they said flashing the computer would help. Just curious if it works for a vehicle with that many miles on it, or if it may be a more serious problem.

 

The mileage doesn't matter - the flash changes how the computer works and what it tells the transmission to do. How hard is hard? 1st gear is very low, so there's a noticeable shift there regardless of flash or transmission performance.

 

Its more of a jolt. Jerks the truck a bit some times.

 

I'd start by pulling the ground cable off the battery and letting the truck sit for 15 minutes or so... let the transmission computer reset and go into adaptive relearn. There's some chance this is just a learned behavior.

If that doesn't work, make an appointment to get the TCM flashed up.

 

Thank you I will try that and see if it works.

 

There are a few TSBs related to the issue(s) that you describe and the recommended fix is a flash of the PCM for the latest level/version, followed by an adaptive shift strategy relearn.