When i am driving my truck the engine seems to go flat, low power and low rpms(1000+) when it goes into 4th locked (OD). Any ideas why. When i give a slight gas increase, the rpm's slowly rise then jump up and unlock the converter and carry on. Whats going on, are the 5.4L's all sluggish in low RPM OD?
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Any altitude changes? I had a similar problem when I went to Colorado over Christmas break.

 

All vehicles that are factory tuned for gas mileage will have similar behavior - it wants to get into OD and lockup as soon as possible. This can be improved considerably with a programmer and custom tunes. You may be able to improve things somewhat by disconnecting the battery to clear the adaptive learning.

 

I use that button a lot myself.

 

Mine does the same exact thing. I've made it a habit to drive with my OD off when I'm around town because of my 3.55 gear ratio. At town speeds it always seems to be in between gears and I know it's gotta be hard on the engine and transmission never finding a sweet spot to stay in.