I had 4.10 gears installed on friday (awesome mod btw), and I was going to use my predator to reflash the speedometer. My understanding was that I just needed to adjust the Axle Ratio. I did that, twice, but my speedometer is still registering at least 18 mph higher than my actual speed. Am I missing something? Its an automatic too, if that makes a difference.

 

Well, I called my ford dealer yesterday and asked them if they could recalibrate my speedometer. They said yes and that it would cost me $92 to have it done. I got up early this morning and was the first one there when the service department openned. An hour later and $92 spent, I started to drive home. The speedo was still registering 15-20 mph faster than actually speed. I pulled into my driveway and called the service department at the Ford dealer and explained my dissatisfaction and irritation that my speedo problem wasn't fixed. Long story short, after my discussion with the service manager, they refunded my $92 dollars.

Now, I'm still stuck with a speedo that isn't calibrated correctly. The service manager at the dealership referred me to a Aamco Transmission shop and told me to ask for one of their automative techs that has "experience" fixing this problem. The tech I asked for wasn't there, so I talked with another guy. He said I needed a "box" or possibly new gears in the speedo to correctly recalibrate the speedo.

I could use some advice on this.
#1 - Its been my understanding that the speedometer in late model mustangs were computer controlled and that a gear change wasn't necessary. Supposedly, by using my DiabloPredator to reflash the EEC with the correct axle ratio, my speedo problem would be fixed. That hasn't been the case.

#2 - The only "box" I know of that corrects the speedo is the SpeedCal from Dallas Mustangs and it only works on 5 spd manual mustangs. Mine is a automatic. So, if there's another "box" out there that will help, please let me know.

#3 - At this point, I'm of the mind to just get one of my friends in a chase car and use a Sharpee to mark the speeds on my instrument panel lol. The biggest downside to that is I'll be racking up huge mileage on my odometer.

Any suggestions or solutions would be extremely welcome. Thanks

Joe.

 

Just get a dallas speed cal it's simple and cheap, or dump your predetor and get an sct.

 

I was going to do that, but I was told by the shop that did the gear install, that the Dallas SpeedCal only worked on 5spd manual mustangs and not automatics.

 

give kevin a call a motion dynamics, he can help you out

 

Hehe, Motion Dynamics in Pf-ville were the ones that did the gear install. Kevin was the one that checked with Dallas Mustang to see if their SpeedCal will work with an auto.

 

yeah they did my whole setup including the sct tuner

 

FFRP sells a calibrated. Not sure if it's just for manuals or autos but you can try that.

 

Thanks, I'll give that a looksy, much appreciated.