Hello,
I've owned my 06 Dakota 4.7 with the 45rfe for about 3 years and would give my left pinky finger for one more gear on the highway. It runs at about 21-2300 rpm at 75-80 mph. Ive seen threads elsewear about jeep TCM's being able to be utilized in this manner on older Dakota's . I'm really not in the mood to fry my ECU to gain a few mpg's, but another gear sounds real nice. Any body have some suggestions or input?
Thanks
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Not sure that it gives you a deeper overdrive gear, but, yeah, folks have swapped the TCM for that additional gear. There are a few threads about that in the Dak section.