Speedo Gear Information

[Notch93]

Manual Transmissions with 6 Tooth Drive Gear



Not found in OEM applications



Item Number
Description
N/A
3.08 Gear Ratio / Not possible

C0DZ-17271-A
3.27 Gear Ratio / Maroon 16 Speedo Gear

C3DZ-17271-C
3.55 Gear Ratio / White 17 Speedo Gear

C0DD-17271-B
3.73 Gear Ratio / Yellow 18 Speedo Gear

C0DZ-17271-B
3.90 Gear Ratio / Pink 19 Speedo Gear

C1DZ-17271-A
4.10 Gear Ratio / Black 20 Speedo Gear

C4OZ-17271-A
4.30 Gear Ratio / Red 21 Speedo Gear



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



Manual Transmissions with 8 Tooth Drive Gear



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



Item Number
Description
C0DD-17271-B
2.73 Gear Ratio / Yellow 18 Speedo Gear

C1DZ-17271-A
3.08 Gear Ratio / Black 20 Speedo Gear

C4OZ-17271-A
3.27 Gear Ratio / Red 21 Speedo Gear

Jeep Part #j3167393
3.55 Gear Ratio / White 23 Speedo Gear

Jeep Part #j3167393
3.73 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.)

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.)



Automatic Transmissions with 7 Tooth Drive Gear



1983-1989 Automatic Transmissions



Item Number
Description
D0AZ-17271-A
2.73 Gear Ratio / Blue 16 Speedo Gear

C7AZ-17271-B
3.08 Gear Ratio / Gray 18 Speedo Gear

C7VY-17271-A
3.27 Gear Ratio / Tan 19 Speedo Gear

C8SZ-17271-B
3.55 Gear Ratio / Orange 20 Speedo Gear

D0OZ-17271-B
3.73 Gear Ratio / Purple 21 Speedo Gear

Jeep Part #j3167393
4.10 Gear Ratio / White 23 Speedo Gear



Automatic Transmissions with 8 Tooth Drive Gear



1990-1998 Automatic Transmissions



Item Number
Description
C7AZ-17271-B
2.73 Gear Ratio / Gray 18 Speedo Gear

C8SZ-17271-B
3.08 Gear Ratio / Orange 20 Speedo Gear

D0OZ-17271-B
3.27 Gear Ratio / Purple 21 Speedo Gear

Jeep Part #j3167393
3.55 Gear Ratio / White 23 Speedo Gear

Jeep Part #j3167393
3.73 Gear Ratio / White 23 Speedo Gear (Not 100% accurate.)

Jeep Part #j3167393
4.10 Gear Ratio / White 23 Speedo Gear (Not 100% accurate.)



Now if you really want to change the internal drive gear of your manual tranny you can match it according to the table below. Be aware that the 6 tooth will offer the most combos for numerically higher gear ratios and offer the greatest degree of accuracy. The 6 tooth gear selection table for a manual tranny is the first in the page.


Item Number
Description
E3ZZ-17285-B
6 Tooth Internal Drive Gear / Black

E3ZZ-17285-A
7 Tooth Internal Drive Gear / Yellow

F0ZZ-17285-A
8 Tooth Internal Drive Gear / Green

[SPeace-ATL]

Thanks Notch93!

This is all great information.

The part numbers for the internal T-5 6t, 7t, and 8t gears are as follows:

6-Tooth Black:
E3ZZ-17285-B

7-Tooth Yellow:
E3ZZ-17285-A

8-Tooth Light Green:
F0ZZ-17285-A



Also, that 23-t Jeep gear doesn't mesh very well and will eventually tear up and can even wear out the internal gear. I have attached a picture of a damaged 23t gear and a worn out 7-t gear as an example.

Being such a project to actually open the T-5 to replace the internal gear many people choose to use the 23-t gear and replace it every few months...

http://inlinethumb17.webshots.com/47632/2297289880105779303S425x425Q85.jpg (http://good-times.webshots.com/photo/2297289880105779303mvLPek)

[90coupe]

What about if u replace ur t5 with a 1972 c4 with 373 gears in the car?

[big block]

What about if u replace ur t5 with a 1972 c4 with 373 gears in the car?

http://www.cjponyparts.com/SPEEDOMETER-DRIVEN-GEAR-TYPE-3-23-TOOTH-AOD-AND-AODE-AUTOMATIC-TRANSMISSION/p/HW1295/

part # HW1295

i ran it in my c4 and now im running it the 4cyl transmission, before it was way off 45 would be 57 and now with the new gear, 48 is now 50 its only off by 2 and that's calibrating it with a gps

[1992vert]

:patriot:

[90coupe]

Thanks for the info

[91twinstang]

Originally: 1991 LX 5.0L

I have been trying to figure this out for awhile, but I am lost on this.

How much do you think my speed will be off from a 91 AOD to an 89 T5 with the stock 2.73's?

What speedo gear would I need to correct this?

[SPeace-ATL]

Originally: 1991 LX 5.0L

I have been trying to figure this out for awhile, but I am lost on this.

How much do you think my speed will be off from a 91 AOD to an 89 T5 with the stock 2.73's?

What speedo gear would I need to correct this?

An 89 T5 with a 2.73 rear end should probably have a 16t gear on the VSS sending unit.
A 90 or newer transmission would need an 18t gear on the VSS.

Things like tire size will make it vary by a tooth or so, but this should put you pretty close.

[big block]

Originally: 1991 LX 5.0L

I have been trying to figure this out for awhile, but I am lost on this.

How much do you think my speed will be off from a 91 AOD to an 89 T5 with the stock 2.73's?

What speedo gear would I need to correct this?

im going to have to say it will be HW1277 its the only 16t 5speed gear that cj's has, besides the 16t 4speed top loader, now that is based off that the t5 you have is an 89

http://www.cjponyparts.com/SPEEDOMETER-DRIVEN-GEAR-TYPE-3-16-TOOTH-AUTOMATIC-AND-MANUAL-TRANSMISSION/p/HW1277/

[91twinstang]

im going to have to say it will be HW1277 its the only 16t 5speed gear that cj's has, besides the 16t 4speed top loader, now that is based off that the t5 you have is an 89

http://www.cjponyparts.com/SPEEDOMETER-DRIVEN-GEAR-TYPE-3-16-TOOTH-AUTOMATIC-AND-MANUAL-TRANSMISSION/p/HW1277/

I will double check on the year of the T5 in a few min, but would this still be the correct gear since it has 17" wheels?

[big block]

I will double check on the year of the T5 in a few min, but would this still be the correct gear since it has 17" wheels?

im unsure about the wheel sizes i roll stock :yes1:

[Chuckles_5.0]

\
Also, that 23-t Jeep gear doesn't mesh very well and will eventually tear up and can even wear out the internal gear. I have attached a picture of a damaged 23t gear and a worn out 7-t gear as an example.

Being such a project to actually open the T-5 to replace the internal gear many people choose to use the 23-t gear and replace it every few months...

http://inlinethumb17.webshots.com/47632/2297289880105779303S425x425Q85.jpg (http://good-times.webshots.com/photo/2297289880105779303mvLPek)

Is that just an issue with the JEEP part? LRS has a 23-t gear that is notably different. Can I assume that it will not have the same issue was the Jeep gear?

http://c1385782.cdn.cloudfiles.rackspacecloud.com/lrs-17271d-k_7970.jpg

[NC STANG GUY]

You'll have that issue with about any 23 tooth speedo gear. Just plan on replacing it every so often.

[Chuckles_5.0]

Can I expect some notice as to the gear going bad (needle dancing a bit / not smooth motion)

I guess it makes sense, the 23-t makes for some pretty small teeth on that thing...

[NC STANG GUY]

Can I expect some notice as to the gear going bad (needle dancing a bit / not smooth motion)

I guess it makes sense, the 23-t makes for some pretty small teeth on that thing...

Most of the time it'll make the speedo act up.

[sgs2523]

Thanks for this I have been looking for a part number my speedo is about 20mph off in my Capri.

[Chuckles_5.0]

Thought I would through this in here, I found it while trying to figure out what gear I would need running the taller tires out back.

Effective Final Drive Calculator (http://www.4lo.com/calc/geartire.php)

simply plug in the Ring and Pinion ratio and then the stock tire height and new tire height and it will give you your effective final drive ratio, use this to determine which driven gear you need.