speedometer off by getting regeared?

[metstalker]

alright guys i have a little problem when i finished putting bigger tires on my explorer i decided to see how off my speedo was it ended being off by 1/10 of a mile that wasnt that big of a deal and i had been on the interstate to see how i compared to other cars. but since i got regeared from 3.08 to 3.73 i noticed that i was going 80 miles on the interstate yet i was getting passed like i was going the speed limit. either way i was just wondering if getting regeared affected the speedometer.

 

[Blee1099]

You need to change the speedometer gear.

 

[metstalker]

alright how do i do this

 

[metstalker]

i searched and found that the gear is in the transfer case but im 2wd and dont have one

 

[BLUE OVAL]

you need to slow the speedo down if your speedo is reading to fast by using more teeth on the speedo gear
to do this you need to know what gear you have in there now by taken the gear out and counting the teeth or call you local ford dealer the dealer will ask you tire size axle ratio and trans type the least amount of teeth the dealer will sells is 16 and the max is 21
my 94 ex had 235/75/15 327 gears a4ld trans i think all those years only used that size of tire my speedo gear was 17tooth when i installed my 32's my speedo was out by by 8kmh at 100kmh so my speedo read 92 kmh in order to speed up the speedo i would have to use a lower tooth speedo gear but when i changed to 373 gears yhis corrected my speedo it only out by 3kmh reading 103kmh when i'am only doing 100kmh
putting less number teeth speeds up the speedo and more teeth slows the speedo down
hope this helps
dale

 

[Creager]

ford used to use a color coating system (unfortantly they dont anymore) for their speedo gears.

Manual Transmissions:

16-teeth-wine(C0DZ-A)

17-teeth-white(C3DZ-C)

18-teeth-yellow(C0DD-B)

19-teeth-pink(C0DZ-B)

20-teeth-black(C1DZ-A)

21-teeth-red(C4OZ-A)

Auto Transmissions:

16-teeth-blue(D0AZ-A)

17-teeth-green(C7SZ-A)

18-teeth-gray(C7SZ-B)

19-teeth-tan(C7VY-A)

20-teeth-orangeC8SZ-B)

21-teeth-purple(D0OZ-B)


i think you want a 17 tooth gear. maybe 18.

 

[metstalker]

yeah but i need to know where i can get to this gear general location. but thanks for the info

 

[Fantasymon]

If your speedo says you are going faster than you are actually going then you should fix it asap. It will make your odometer count more miles than you are actually going.

My speedo says I am going slower than I actually am (mainly when going above 65mph). So-- my odometer counts less miles than actually traveled.

 

[dreamr]

yeah but i need to know where i can get to this gear general location. but thanks for the info

In the 2wd models I believe it is located in your transmission. Look for a sensor plugged in down there.

 

[bmxking5]

I too think that the gear is in the tranny.

 

[Creager]

i think it might be along the tail-housing on the tranny. i remember seeing it in the hanyes manual.

 

[metstalker]

thanks guys ill thats all i needed and finals are over now ill have time to work on the explorer

 

[Creager]

it wont take you long to do this =)

if worse comes to worse use a haynes manual

i project about 20 minutes at the most to do this haha.

 

[metstalker]

thanks guys ill post if i have problems