New gears = Messed up Speedometer

[imported_Sleeper]

@BlueZ06

I’m pretty sure you’re speedometer is electronically controlled on the 2004. You’re going to need to retune to fix the speedo. I know my 2004 Mach 1, I had to reprogram it only when I switched to 4.30s

Purchase a pocket programmer, or goto a place that offers dyno tuning.

I know the older style SN95’s (94-98) could correct this issue with a proper speedo tooth gear size. May want to double check and see if you can just do this instead. I think they cost about $80

oops, wasn’t sure what he meant adn now i do, what about laurel mountian stangs? couldnt they reprogram it?