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Topic: gears and posi help! (Read 2155 times) previous topic - next topic

gears and posi help!

well, my father knows some stuff about cars. and he said if the gears in the trany and the gears in the rear end arent the same, the trany or the gears will break. is this true? or do i just need a speedometer thing to out in my trany so it will read the right mph.
oo by the way, where can i get a thing to out in my trany to tell how fast im going with 3.73 gears?
1988 LX coupe. a dressed up motor with full exhaust and BBK shorties with flowmasters, BBK CAI, accufab 65mm tb, HO upper intake, cobra valve covers.

gears and posi help!

Reply #1 –
I wont come between dad and son things but this might help,,,,,



eves drop in on an old topic i have in my saved goodies,,,,,,,,,,


MISC SPEEDO GEAR INFO
---thunderjet302
For those of you who have installed 3.73 gears with your stock AOD you know how hard
it is to find a speedo driven gear to make your speedo close to accurate. In reality a
24 tooth gear would put it dead on but a 23 tooth gear makes it with in 1-3 mph of being
correct. The only problem was that there was no 23 tooth auto trans driven gear avaliable
from Ford. You either had to use a 21 tooth gear like I did and accept the 6-7 mph
difference between what the speedo said and your actual speed or use a 23 tooth gear
for a T-5 which would wear out fast. There is a solution though. I found a 23 tooth
AOD driven gear at Mustangs unlimited. I ordered it and it looks just like my 21 tooth
gear with 2 more teeth. I installed it and vola my speedo is almost right on. Here's
the link if anyone is interested.  ---thunderjet302

--turbocoupe50
Cool... But I have the later super coupe AOD with a 7 tooth output.
A 21 works fine for me.--turbocoupe50

gears and posi help!

Reply #2 –
Ok dont mean to hijack but: How can you tell what drive gear you have without taking the tailshft housing off? Is there a way to tell? I know the trans in my car has been swapped and i think the trans in it came from a Mustang but im not sure. Thanks

gears and posi help!

Reply #3 –
so the tranny and the rear end gears dont have to match?
1988 LX coupe. a dressed up motor with full exhaust and BBK shorties with flowmasters, BBK CAI, accufab 65mm tb, HO upper intake, cobra valve covers.

gears and posi help!

Reply #4 –
Nope, just the rear gears and the speedo gear.


Scott
1980 birds X 3, 1982 bird, 1984 XR7, 1988 TC

gears and posi help!

Reply #5 –
ok thank you!
1988 LX coupe. a dressed up motor with full exhaust and BBK shorties with flowmasters, BBK CAI, accufab 65mm tb, HO upper intake, cobra valve covers.

gears and posi help!

Reply #6 –
Alittle off topic, how hard is it to put in the speedo wire itself. My speedo doesn't work after we had to drop the trans for the flexplate. I *think* it may be the wire but maybe just a new speedo gear?

gears and posi help!

Reply #7 –
Quote from: 84 Fila;118434
Alittle off topic, how hard is it to put in the speedo wire itself. My speedo doesn't work after we had to drop the trans for the flexplate. I *think* it may be the wire but maybe just a new speedo gear?

The wire is like any other wire, find it, splice, solder, done.
It's Gumby's fault.

gears and posi help!

Reply #8 –
On, the paice that the speedo gear goes on. Say speedo cable insted? If not would a pic help?

gears and posi help!

Reply #9 –
SPEEDOMETER "DRIVEN" GEAR BLACK 23-TEETH W/ AT
Speedometer "Driven" Gear, 23-Teeth Black, for Ford Automatic Transmission.

Nylon 23-teeth black speedometer "driven" gear. Commonly used with 7-tooth speedometer "drive" gear and 4.10:1 rear axle ratio.

This is the gear located on the speedometer cable.

Related Parts:
-Speedometer Gear Clip, #F1151
1988 LX coupe. a dressed up motor with full exhaust and BBK shorties with flowmasters, BBK CAI, accufab 65mm tb, HO upper intake, cobra valve covers.

gears and posi help!

Reply #10 –
is that the only thing i need to go along with my gears?
1988 LX coupe. a dressed up motor with full exhaust and BBK shorties with flowmasters, BBK CAI, accufab 65mm tb, HO upper intake, cobra valve covers.

gears and posi help!

Reply #11 –
if i owned your car,,, i would pop out the speed sensor and swap in a new / different plastic gear.

so your right on track man,, just do that easy task and see what happens.  tom or thunderchicken may know right off the bat the exact ford PN,,
anyone know the pn he needs?


84FILA
im not sure what you are getting at but if you are saying you have a cable type speedo then look underneath an early 90s bronco or pickup and you'll see how that speedo transitions a cable drive type speedo into an electric sensor as well.  that will be the part you need , it will accept a cable and create an electrical output for your dash.  Dont ask me if it will work cause id be like you,,,experimenting.  now stop hijacking this thread,,,,LOL

gears and posi help!

Reply #12 –
oh yeah,,
its TRAC LOCK (ford)
not chevy posi:grinno: :beatyoass:

gears and posi help!

Reply #13 –
My 86' Bird has the speedo wire and the electrical sensor for the computer as well.


86' T/C 4.6L DOHC
16' Chebby Cruze 1.4L Turbo
17’ Peterbilt 389 600hp 1850ftlb Trq 18spd

[SIGPIC][/SIGPIC]

“Heavy Metal Mistress”
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gears and posi help!

Reply #14 –
so i need the speedo wire and electrical sensors too?
1988 LX coupe. a dressed up motor with full exhaust and BBK shorties with flowmasters, BBK CAI, accufab 65mm tb, HO upper intake, cobra valve covers.