The worst tranny of my experience was the 6sp in the 2009-2010 F150. No select option and no OD lockout. I towed a 7300lb TT, had the 5.4 with 3.73 gears. I swear it would shift at the site of it's shadow. When going a typical overpass on the interstate runnng 60-65mph it would drop from 6th to 4th then back to 5th, then 6th and sometimes back to 5th if there was a little headwind.
If it had the select shift like the 2011 it would've been fine.
It also had the common tranny bump when coming to a stop from 2nd to 1st. It felt like someone tap the back of the truck. Then it would sometimes bump on accelerating from a stop. Took it to the dealer twice. 1st trip was a flash and the 2nd trip they told me to just drive it since it's still under waranty and when or if it breaks they'll know what to fix. Really?
