I have an '08 w the 6.4 just under 91000 miles. I just bought it a couple months ago. I did the dpf delete and I'm using the Gearbox Z dpf-r+ tune. I have their Electron monitor as well. Truck runs great and shifts great 99% of the time. The issue I'm having is I feel it goes into higher gear too soon, and unless I really plant the throttle it doesn't downshift. Any ideas or suggestions on this? Is it a common thing? I don't know when or even if the trans was serviced, I'm doing that this weekend. I don't know if this will help though. Thanks
Servicing the trans is a good thing, but it won't help this. The decision on when to shift, either up or down, is 100% in the computer. The tunes control all of that. Servicing the trans doesn't do anything for the computer.
Mark Former Ford Automatic Transmission Engineer
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