Speedometer
- Thread starter JimKing
- Start date
How do I determine what ratio I need and or where do get a re-calibrator
cobrajeff96
Well-Known Member
cobrajeff96
Well-Known Member
Which means your car probably has a 3.08 rear gear.
Do you have manual or auto? Check for the code either on the differential casing or the driver side door sticker to find out which rear gear you have.
Check this thread, too: https://www.sn95forums.com/threads/gear-ratio-change-speedometer-correction.88375/#post-1588221
A speedo calibrator you can find for example at LMR:
I looked into it and by the way, It's an automatic...
I have another question…I’ve been restoring the car (94 GT) I bought from my sister for the past year. I found a box in the left rear corner of the trunk near the taillight. I believe is for communication with a key fob for the remote to lock and unlock the doors. She says she never had one. With this…I notice my anti-theft warning light comes on, on the dash shortly after driving for a few minutes. Is this what that box is for and is this the reason why the light comes on? If so, what are my options. Also, back to the speedometer...my odometer and trip odometer don't work either. I imagine this just the gears?. I'd like to address both issues when I have the dash apart if you know what I mean.
I'm new at this forum. How do I reach out to more subscribers?
jim
RAU03MACH
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your asking wheel size not the gear
right
if it is wheel or tire size do you have the size
right
if it is wheel or tire size do you have the size
I was talking about the gears in the dash for the odometer. I did buy a new set but, I haven't installed them yet. As for the wheels, I believe they are 18x9 Bullitt Wheel & Lionhart All-Season LH-503 Tire Package from American Muscle. I’m not at home but I’ll check later.
RAU03MACH
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Does anyone know how to set my speedometer to the correct speed after changing the wheel diameter on a 1994 Mustang GT
jim
jim
RAU03MACH
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how tall is the tire
RAU03MACH
Legend
32.6 inches tall
so the sheet at the top with tire ratio
31 is as high as it goes
so id go with your gear ratio witch 308 could be
but it shows N/A
i would try the black one if it in the car already that will be as close as you can get
or try this electronic speedometer recalibrated. as mentioned,
so the sheet at the top with tire ratio
31 is as high as it goes
so id go with your gear ratio witch 308 could be
but it shows N/A
i would try the black one if it in the car already that will be as close as you can get
or try this electronic speedometer recalibrated. as mentioned,
RAU03MACH
Legend
the one that was posted above
by cobrajeff96
read a little bit
by cobrajeff96
read a little bit
SPeace-ATL
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The calibration gears are in the transmission at the VSS Pickup and not in the speedometer.
From 1994 through 1998 there is no speedometer cable and the calibration is performed by changing the gear on the end of the VSS Pickup and for a Manual transmission the gear on the output shaft inside the transmission can be changed. For the AOD Automatic that internal gear an 8-tooth gear and it is machined into the output shaft so there are no options other than the small gear on the VSS Pickup.
Thus, the electronic recalibrator is often needed with a differential gear change. Just a tire size change MIGHT be addressable by changing the small gear on the tip of the VSS Pickup.
I want to add that a 21t gear is the highest tooth count for these cars.
People are finding 23 tooth gears on the internet, but Ford never offered these because the gear teeth are paper thin and will not hold up.
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