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  • 1979 - 1995 (Fox, SN95.0, & 2.3L) -General/Talk-
  • Fox 5.0 Mustang Tech

Speedo is 15mph off.

  • Thread starter Thread starter 88 Fox GT
  • Start date Start date Jun 23, 2006

88 Fox GT

Active Member
Nov 18, 2002
1,674
0
36
Iowa
Jun 23, 2006
#1
  • Jun 23, 2006
  • #1
Got pulled over for doing 65 (in a 55 while speedo said 50). Luckily the cop said I had a nice car and stuff like that and I had a clean record and he believed me about the speedo because I was being honest and courteous to him. So, he said he wanted to keep my record clean and he let me go.

Now, it's time to figure this **** out incase I run to some a-hole cop next time. If I recall correctly, last time I checked my speedo gear it was red and I counted 21 teeth. According to this chart, that's for 3.73 gears.

Manual Transmissions with 7 Tooth Drive Gear

1983-1989 T-5 OEM
Pre 1993 T-5 Aftermarket
1996-1998 Cobra T-45 OEM
All Tremec Transmissions

Item Number
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
Click to expand...

This chart also says I should be using the maroon 16 tooth gear for my 2.73 gears. I don't know how it got the wrong gear in the first place unless at some point they had 3.73s in it. I just want to get the right gear in it until I get my other rear end and install my 3.73s. Would the 21 tooth make my speedo 15 mph too slow if it's supposed to be a 16 tooth?
 

Jaswir

Member
Mar 31, 2005
578
0
18
Orlando, FL
Jun 23, 2006
#2
  • Jun 23, 2006
  • #2
yea... if you have 2.73 you need to put the 16th one back in... it would make it that much off...

i myself have the same problem... when im doing 70mph im going 85! i put a need speedsensor and i have the right gear but still is off... i dunno what my problem is!
 

trbkrb

Founding Member
Jun 4, 2001
1,976
4
39
Houston, TX
Jun 23, 2006
#3
  • Jun 23, 2006
  • #3
I've got one I'll send you, PM me your address.
 

Roland69

Sergeant Tangnet
Sep 17, 2005
2,867
2
58
Port Elgin, Ontario
Jun 24, 2006
#4
  • Jun 24, 2006
  • #4
I will have one you can have as soon as I get around to puting the black 20 tooth one in mine
 

Jaswir

Member
Mar 31, 2005
578
0
18
Orlando, FL
Jun 24, 2006
#5
  • Jun 24, 2006
  • #5
takes 5mins... lazy ass!!2 ^^^^


j/k!
 
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