Transmission light and rough idle
 

I have a 2005 F-150 XLT with K&N CAI. I do a lot of highway driving and recently I have been getting a blinking transmission light and the truck starts shaking until I let off the gas and go down to about 50-55mph. Also when I get off the highway and I'm at a stop light or sign the engine has a rough idle and has even died sometimes but starts right back up. Any ideas? I have only had this truck for about 40 days.

Fuel filter comes to mind. When was it last changed? What is your current mileage?

Several other things can cause a rough idle....I'll assume you have no stored trouble codes indicating a bad coil pack. Dirty injectors, a bad plug(s), carbon build up in the throttle plate of the throttle body, or a intake/vacuumn leak. All these have been discussed here on this forum as potential poor idle culprits.

thanks i'll take a look at some of that