1987-1993 T5 ( manual trans * )
Speedometer Cable & Speed Sensor info
. In This Section...
1 Info on Speed sender & plastic speedo gear
2 How to change speedo cable


Speed Sensor

CAUTION !
Let the car cool down, you will be working next to the exhaust, headers, and directly with the transmission.
When jacking the car up use jack stands to safely secure the car

Before I get into the cable replacement I just wanted to get the stuff about the sensor out of the way...

This is the VSS
or speed sensor

It plugs directly into the transmission.

- This is where the the speedometer cable plugs into

- also gives cruise control speed information.

The sensor is "plugged" into the transmission and held on by one small bolt.

Notice the Yellow Gear?
That's the gear that is changed when different size tires/rims are used.

When different size tires are used the speedo will not read accurate because the tires now spin at a different speed
(take longer to complete 1 rotation with larger tires/rim combo) or vice versa.


- How to Remove Sensor...

Once the bolt is removed, and the wire harness pulled out,
the sensor can be gently pulled out, the speedo cable can still be connected at this point.
Since the car is cool...nothing should leak out.

Pull the speedo cable out. That's it?

Well yes, it took me a few minutes to figure how to get it out of that retaining clip, and a quick strait pull did it. That's also the way to put it back in.

- Put it Back / Sensor Replacement...

It seems best to replace this without the speedo cable. With the cable on it is hard to put the sensor into the transmission strait. Gently push the sensor into the trans until fully in, if it doesn't feel right back it off and try again, it should go in the first time but just make sure the gear is seated nicely. Bolt it in, (not too tight, you will strip the bolt or trans here) plug the wire harness in then push the cable in until it clicks past the clip. I put the cable in loose then snapped it in by pushing its lip in with a screwdriver,


notes...

- My old speedo cable had melted and seized up.

- I replaced the cable and still no speed readings.

- It turns out that when the cable seized, the transmission spun the plastic gear (yellow on the sensor) and it spun itself/rounded out the square hole it connects to the cable with .

Old gear.

Notice the INSIDE hole has rounded

NEW gear.

The INSIDE hole is SQUARE

- I would recommend that you at least check the plastic gear for wear, inside & out. Just pull the clip out and pull the gear off the sensor.. try remember which way the clip was positioned, I think it was fat side down.


Replacing the 'Yellow' Gear
In my case it was yellow (18 teeth) to match the 308 rear end. The gears seem to be color coded, so if you pulled out a yellow one order the yellow one. Just in case I would count the number of teeth just to make certain.

Funny how the parts guys (idiots) at the ford dealer couldn't figure out which one to order for my car, even with the info I had...Thats ok you know what to do now!

The link below has a list of which gears were in every fox mustang

FYI
Because there are different rear axle ratios and other factors such as tire size, and changes in manual transmissions during the years there are different gears & shapes.
There is a Yellow that is 18 tooth and a gray that is also 18 but different shape.

Updated 7/11/03



More Info

Found sites with more info on gear ratios and these gears:..

Nothin' But Notchbacks Link

Where to buy?

One place to get a new gear (abou $10) is from Steeda.com.
Under..."Speedometer Recalibration Gears"


Speedo Cable


All I can say it that you need patience. Plugging the cable into the speed sensor at the trans is easy and so is routing the cable to the firewall. Plugging it into the speedometer in the dash is another thing.

It looked as if I was able to disconnect the old one and plug the new one from under the dash until I actually tried it. I opted to take the dash apart

Your actually not removing the whole dash,
just the bezel or console
that is above the steering wheel, that houses the speedo & gauges.

 

Its really just remove all the screws (torx & philips). Your going to need a L shaped philips to remove the 2 screws that are under the windshield, you have only about 2inches of room here. Other than that I was more concerned with doing the job than taking pictures, just remove the pieces & keep the screws with the right parts and installation will be easy. Its an easy job but takes a while. You will have to remove the headlight & hazard switches & unplug them too.

 

The old cable pulls out and the new one plugs in..thats it.

 

 

 

*may be different for automatics & other years

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