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  • 1979 - 1995 (Fox, SN95.0, & 2.3L) -General/Talk-
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speedo gear ?

  • Thread starter Thread starter misterskin
  • Start date Start date Nov 18, 2008

misterskin

New Member
Nov 11, 2008
6
0
0
Arkansas
Nov 18, 2008
#1
  • Nov 18, 2008
  • #1
I have 4.10 gears in my auto 87. I bought a new speedo gear to correct my spedometer with the new gears. Well, we installed the gear today and I took a little test ride....less than a mile. It was working fine. Parked the GT and helped a buddy work on his SVO for an hour or so. Got back in the GT and the speedo was D.O.A......nothing! Drove all the way home, 15 miles or so, and it never moved again. What the hell?
 

4G-KDMP

10 Year Member
Jul 23, 2005
935
19
39
CA
Nov 18, 2008
#2
  • Nov 18, 2008
  • #2
If everything is still bolted in place then possibly a

View attachment 289912
 

misterskin

New Member
Nov 11, 2008
6
0
0
Arkansas
Nov 18, 2008
#3
  • Nov 18, 2008
  • #3
dont say that.

that's kinda what I was expecting. I was just hoping if I asked that somone would fill me with false hope. lol
 
F

FoxChasis

20+ Year Stangneter
Dec 23, 2003
589
276
93
Nov 22, 2008
#4
  • Nov 22, 2008
  • #4
The 23T driven gear is a POS.

An '87 AOD already has a 7T drive gear on the output shaft, and that's as low as they get. No such animal as an AOD output shaft with a 6T drive gear.

Your only way to deal with it is to have a speedometer repair shop install a speedometer 'reducer' box inline with the speedo cable. You could have the shop recalibrate the speedometer for your combo but if you change anything (transmission, tire size, rear gear), it'll be off again.
 
H

habiv

Member
Oct 28, 2004
125
1
16
Nov 23, 2008
#5
  • Nov 23, 2008
  • #5
I had the same problem when I replaced mine this summer. Did you check to make sure the cable is working? If you take it out and spin the gear on the end of the cable the spedo should jump. When mine stopped working, it was the little clip that holds the interior gear in place broke when I hit a bump. Apparently they are crap and they break all of the time. Good luck with it.
 
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