Re: 2003 F250 Hard shift out of Second
The trans does shift 3-5. But many people call it the 3-4.
I don't know what backpressure is for a shift. I've never heard of it. And I developed the factory tunes on the 2005 5R110W diesel F-Series. So I don't know what to tell you about that.
Former Ford Automatic Transmission Engineer
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