I have problems with my speedometer reading the mph correctly, im out of ideas on what to do, this is what i have, my mustang was a v6 manual when i first bought it, then i swap engine ecu with engine and fender harness (dash harness stays the same v6 one), cluster from cobra, manual tranny, irs, etc.. From an 01 cobra, until now speedometer working fine, now i swap the engine for a 5.4 32v with same manual tranny, was a swap of plug and play, same ecu same harness just swap engine amd tune, then i swap the tranny for an automatic 4R75w with 3600 stall and manual valve body, everything is working good, its tuned, but we cant make our speedometer read correctly on the cluster, but the ecu reads it correctly, cause checking it out with my tuner on the laptop it reads correctly, but on my cluster reads a lot more, so i dont know if something its sending the bad pulse from the ecu to the cluster or something, thanks in advance
