also would like to know

 

23 tooth speedo gear, its not exact, but as close as you can get.

 

23tooth is for 8 tooth gear, and 21 for 7 tooth, and 19 for 6 tooth, but i believe 93 cobra t-5 had 7 tooth didnt it?

 

I firmly believe that it was the 23 tooth gear I had done in the 91'. I just got another one to be installed on my 89' tomorrow.New 3:73's going in.Old 2:73's coming out.New Posi unit rebuild,bearings and etc.Once the clutches get oiled good and dont sqeak-Atco -Look out :joy: ! BTW-yes both cars are t-5's.

 

are there two gears that need to be changed out, or just one?

 

1

 

i would also like to know...i am installing 3.73 and i have a brand new t5 so i am not sure howmany teeth the internal gear has...the tranny i bought is a tremec t5 out of summit

 

Depends on the Transmission's drive gear...

For T5's produced 1983-89 (7 tooth) -> 21 tooth driven gear (Red).
For T5's produced 1990-up? (8 tooth) -> 23 tooth driven gear (White).

The 23 tooth gear is actually a Jeep part and will not be 100% accurate. For more info go here

 

thanx for the replies guys, yeah i had forgotten to state my T5 was out of a 93 cobra

 

I firmly believe that it was the 23 tooth gear I had done in the 91'. I just got another one to be installed on my 89' tomorrow.New 3:73's going in.Old 2:73's coming out.New Posi unit rebuild,bearings and etc.Once the clutches get oiled good and dont sqeak-Atco -Look out :joy: ! BTW-yes both cars are t-5's.

Hey i'm gonna hijack my own thread here for a minute.. yuo are supopsed to wait a while before you run your car after you put in new trak-loc? I rebuild mine and took a 4 or 5 short drives to heat everythign up and let it cool down, then drove 25 minutes to the track a few days later and ran the heck out of my car LOL. The popping had stoped already though. It only took a day for the poppong to stop, I soaked my clutches in frinction moddifier for 10 hours before installing them.

 

one more question, when i pull the speedo gear out to change it, am i gonan loose all my tranny fluid? I havn't changed the speedo gear on a ford tranny yet, and if i am gonan need tranny fluid I need to get it while on the way to pick up my new speedo gear.

 

when you pull that VSS sensor/speedo gear out of the transmission you will be lucky(shall i say unlucky) to have a quarter sized puddle of tranny fluid to fall to the ground. It really doesn't leak at all, especially if you are on a level surface.

 

perfect...thank you hybred... and does anyone know the trueth to the white 23 tooth gear being a jeep part? Or can I get a white 23tooth from ford?

 

I went with a 6 tooth drive gear and a 18 tooth driven gear with my 3.73's and the speedo is as accurate as stock.

 

perfect...thank you hybred... and does anyone know the trueth to the white 23 tooth gear being a jeep part? Or can I get a white 23tooth from ford?

I got mine from 50resto.com...it is sitting right here beside me (23 tooth white gear) to go along with my KC clutch and aluminum driveshaft install this weekend...

 

i kinda want to get mine quick so i am going to go to the dealer to get mine. i am moving in a lil over a week so i have to get it done now or I may not get to get it done for a while.

 

So I am bringing my own thread back to life. I had to do some work on my tranny. It appears the 23 tooth speedo had come all apart I had plastic pieces all through out my tranny. I sugest anyoen else who has 3.73's to change the drive gear on teh out put shaft to the yellow driven gear and the red 21 tooth speedo gear.

 

I have heard the 23 tooth gears break pretty easy because the teeth are so thin. I have a 20 tooth in my T5, but the speedo is still off between 5-7 mph. I may do like sleeper92gt did and go with a different drive gear as well. I just don't feel like pulling a tranny in 40* weather right now.

 

T5 Speedometer Calibration

 

Here's the real deal...The correct speedo gear is going to vary from car to car based on the size of the tires you are running. The formula is the number of teeth on the drive gear multiplied by the axle ratio multiplied by the # of tire revolutions per mile divided by 1000. Not quite sure how you are supposed to calculate the revs. per mile, but with factory tires and 15 in. wheels on my '91 stang it is 815....and no I didn't watch my wheel, I actually called tremec. anyhow, with a 7 tooth drive gear and 3.73's , the correct gear would be 18.65 teeth . Closest you can get is 18 - yellow. ford part # coed -17271-b. get it at your local ford dealer...it's actually cheaper than any aftermarket source.

 

I went with a 6 tooth drive gear and a 18 tooth driven gear with my 3.73's and the speedo is as accurate as stock.

Ditto.