i just did the task of swapping out my clapped out 4.6 in my 97 f 150 4x4 went to a 2000 5.4 that came out of a f 250 2 wheel drive well got the engine in and got running runs awesome took it for its first drive with new engine the other day and all was good until about fifty miles the trans started acting weird like downshifting the instant i let off accelerator pedal then when it upshifts after it starts acting goofy it sometimes slips and bangs into gear or shifts really funny ok would a different tune help my situation or is it a tranny just going bad from the more power the 5.4 produces, never had a problem with the trans when the 4.6 was in front of it now keep in mind i am using the factory 4.6 ecm and torque convertor

 

You need to have her tuned for the 5.4. I'm not sure if that is the cause of the odd trans behavior though.
I would take the truck to a trans shop and have them scan for codes. The professionals have a very high grade scanner which will read trans codes. Also, recheck the plugs to the trans, vss in particular.

 

the 4.6 torque converter has a higher output than the 5.4 but you need a tune for sure

 

i thought i might do you or anybody know the best place to get such a tune?

 

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cool do you have a website for them or a way to contact them?