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Speedo Gear

  • Thread starter Thread starter Calgary351GT
  • Start date Start date Feb 27, 2008

Calgary351GT

Member
Feb 12, 2008
53
0
6
Calgary,Alberta,Canada
Feb 27, 2008
#1
  • Feb 27, 2008
  • #1
I'm running a T-5 with 4.10 gears and 26" tires.

Anybody know what speedo gear I need or where I can get one?
 

87coupe50

Member
Feb 10, 2008
105
1
16
WAYNESBORO, PA
Feb 27, 2008
#2
  • Feb 27, 2008
  • #2
you can check out this site for a speedo gear calculator http://www.sccoa.com/faq/speedgr.html

It seems from your setup that you have an 8 tooth drive gear. A 23 tooth speedo gear would get you the closest, but the calculator says you need a 25 or 26 (which the don't make). You would need to change out your drive gear

Taken from the 5.0 Tech: Technical index: speedo gear part #'s and information
Manual Transmissions with 8 Tooth Drive Gear

1990-1995 T-5 OEM
1996-1998 T-45 OEM Except Cobra

Item Number
Description

Jeep Part #j3167393
4.10 Gear Ratio / White 23 Speedo Gear (Not 100% accurate. This combination will offer the best accuracy without changing the drive gear. Change drive gear to a 6 tooth for complete accuracy. See 6 tooth table.)
 
8

86bluecobra

Advanced Member
Dec 20, 2004
4,265
12
69
B.C. Canada
Feb 27, 2008
#3
  • Feb 27, 2008
  • #3
Yep its the same one as 3.73 gears. Its not accurate with the 3.73 gears aswell. If your into it the t-5 needs to come apart to swap the drive gear out. I'm in the same boat. One day.
 

Calgary351GT

Member
Feb 12, 2008
53
0
6
Calgary,Alberta,Canada
Feb 27, 2008
#4
  • Feb 27, 2008
  • #4
Thanks for the help.

I'm pretty sure the guy that installed my gears put in a 23 tooth. He said I should be close, but my speedo reads about 15% high.
 

TRWXXA

Member
Jan 18, 2003
190
1
19
RIGHT BEHIND YOU!!!... Made you look.
Feb 27, 2008
#5
  • Feb 27, 2008
  • #5
Calgary351GT said:
Thanks for the help.

I'm pretty sure the guy that installed my gears put in a 23 tooth. He said I should be close, but my speedo reads about 15% high.
Click to expand...
Yep. A 15% error is exactly what you'd expect with the 8-tooth drive gear, and the 23-tooth driven gear.

If you replace the 8-tooth drive gear with a 7-tooth gear (yellow), the 23-tooth driven gear will get your speedo reading about 3% slow, which is pretty good.

But as long as you'd be changing out the drive gear, you could look for the 6-tooth (black) drive gear. With the black gear you could use a 19-tooth (pink) driven gear. That would get your speedo almost dead on (according to the theoretical calculations), and the 19-tooth gear would not get chewed up like most 23-tooth gears do.
 
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