I have a 97 Mustang 5 speed transmission, 5.0 engine. I have put larger tires on it. And have changed the rear end, it's a 3.08! I know the odometer is off. Have do I find out what size gear do I need to correct the odometer?? Anyone know how???  

Ford Racing M-4209ADPT-A

Ford Racing Speedometer Recalibration Tool

Corrects Speedometer. Is your Pony's speedometer off because you changed your rear gear ratio or tire size? Then you will need a Ford Racing Speedometer Recalibration Tool to correct your speedometer.

No Reprogramming Needed. The Ford Racing Speedometer Recalibration Tool scales a frequency based on the vehicle speed signal up/down to maintain accurate speed indication to the speedometer and to the PCM with no reprogramming of PCM necessary.

Application. This Ford Racing Speedometer Recalibration Tool will work on the 1994-2004 automatic and manual Mustangs as well as 2005-2010 manual Mustangs. 2005-2010 automatic Mustangs are limited to the equivalent of one step higher or lower gear change ratio (< /- 10% change).

Mustang Fitment: 1994, 1995, 1996, 1997, 1998, 1999, 2000, 2001, 2002, 2003, 2004, 2005, 2006, 2007, 2008, 2009, 2010


how to install it..

http://www.americanmuscle.com/frpp-speedo-recal-9498-install.html  

I was just hoping I could just change a gear, to correct it! I'll have to save up some funds till I can get it! Thank you~!  

I was just hoping I could just change a gear, to correct it! I'll have to save up some funds till I can get it! Thank you~!  

well... you actually might be able to change the driven gear...


pull the speedo housing.. pull the gear off... there is a little clip...

put the housing back in.... to keep dirt out.. and allow you to drive the car if its your only one..


stop by the transmission parts supplier.. after you count the teeth.. sometimes speedo shops will have various driven gears...

usually ratio changes require  both gears to be changes to maintain some kind of contact.. but you have not changed a lot..

the drive gear basic part number is 17271


look it up for this application

97 mustang 4.6L; 3.08 rear axle - auto - P225/55ZR16, P245/45ZR17; Driven gear




the drive gear on the output shaft is the hard one to change...


basic part number  17285 Speedometer Drive Gear

you might be able to just swap the driven gear..  

io found this...

Correct your speedoemeter with one of fords speedo gears, use the table below to figure out which one is right for you.

Speedometer Gear Table

Manual Transmissions with 6 Tooth Drive Gear
Found in

?Not found in OEM applications
Item Number  Gear Ratio  Description  
3.08 Gear Ratio  Not possible  
C0DZ-17271-A  3.27 Gear Ratio  Maroon 16 Speedo Gear  
C3DZ-17271-C  3.55 Gear Ratio  White 17 Speedo Gear  
C0DD-17271-B  3.73 Gear Ratio  Yellow 18 Speedo Gear  
C0DZ-17271-B  3.90 Gear Ratio  Pink 19 Speedo Gear  
C1DZ-17271-A  4.10 Gear Ratio  Black 20 Speedo Gear  
C4OZ-17271-A  4.30 Gear Ratio  Red 21 Speedo Gear  
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~

Manual Transmissions with 7 Tooth Drive Gear
Found In

?1983-1989 T-5 OEM
?Pre 1993 T-5 Aftermarket
?1996-1998 Cobra T-45 OEM
?All Tremec Transmissions
Item Number  Gear Ratio  Description  
C0DZ-17271-A  2.73 Gear Ratio  Maroon 16 Speedo Gear  
C0DD-17271-B  3.08 Gear Ratio  Yellow 18 Speedo Gear  
C0DZ-17271-B  3.27 Gear Ratio  Pink 19 Speedo Gear  
C1DZ-17271-A  3.55 Gear Ratio  Black 20 Speedo Gear  
C4OZ-17271-A  3.73 Gear Ratio  Red 21 Speedo Gear  
Jeep Part #j3167393  4.10 Gear Ratio  White 23 Speedo Gear

~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
 
Manual Transmissions with 8 Tooth Drive Gear
Found In

?1990-1995 T-5 OEM
?1996-1998 T-45 OEM Except Cobra
Item Number  Gear Ratio  Description  
C0DD-17271-B  2.73 Gear Ratio  Yellow 18 Speedo Gear  
C1DZ-17271-A  3.08 Gear Ratio  Black 20 Speedo Gear  
C4OZ-17271-A  3.27 Gear Ratio  Red 21 Speedo Gear  
Jeep Part #j3167393  3.55 Gear Ratio  White 23 Speedo Gear  
Jeep Part #j3167393  3.73 Gear Ratio  White 23 Speedo Gear (Not 100% accurate. This combination will offer the best accuracy without changing the drive gear. Change drive gear to a 6 tooth for complete accuracy. See 6 tooth table.)  
Jeep Part #j3167393  4.10 Gear Ratio  White 23 Speedo Gear (Not 100% accurate. This combination will offer the best accuracy without changing the drive gear. Change drive gear to a 6 tooth for complete accuracy. See 6 tooth table.)  


Automatic Transmissions with 7 Tooth Drive Gear
Found In

?1983-1989 Automatic Transmissions
Item Number  Gear Ratio  Description  
D0AZ-17271-A  2.73 Gear Ratio  Blue 16 Speedo Gear  
C7AZ-17271-B  3.08 Gear Ratio  Gray 18 Speedo Gear  

i am taking that your 5.0 is not a cobra...


with an Manual Transmissions with 8 Tooth Drive Gear


C0DD-17271-B  2.73 Gear Ratio  Yellow 18 Speedo Gear  

if yours is yellow.... buy the black one.. but you might also want to spend the few extra bucks and pick up the red one also.. incase you have changed tire diameters

C1DZ-17271-A  3.08 Gear Ratio  Black 20 Speedo Gear  

C4OZ-17271-A  3.27 Gear Ratio  Red 21 Speedo Gear  

My Mustang had the yellow gear. I ordered a black 20T. Will it work with the gear drive I already have or will I have to change it also?  

yes.. it should fit..   without changing the drive gear on the output shaft..

probably why the electronic ratio device is available.. as thats easier to change a few switches than it is to tear the transmission apart or changing the speedo gear sets.  as you just cannot get there easily with some gear ratios and tire sizes..

have you seen the steam roller tires some people put on them.. 20" 22" 24"  just wait till they hear that you can get a few widths in 27" rims..

at least when you have a flat with those.. all you need it to find your mail man and ask for his pocket full of rubber bands to stretch some new rubber on the rim. .  

Thank you for your HELP! I'm a firm believer in stock wheels. Aftermarket wheels are OK. But there's nothing like a stock wheel. You can go up a size and it changes very little, but when you get up into the twenties, then is when you start having problems!! Thank you again and everyone have a Happy 4th.  

I thought I would let you no .I had the speedometer calculated by a State Trooper. It was right on the money. I couldn't ask for any better! Thank you !