Speedometer gear questions...
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Speedometer gear questions...
Can anyone tell me how many teeth the speedometer gear should have for a '91 F-250? The truck is a 4WD with automatic transmission, (E4OD) 3.55 axle ratios and stock size tires. The current gear is a 19-tooth pink gear. Is there a difference in the gears designed for automatic and manual transmissions or are they identical? Thanks a lot guys.
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Speedometer gear questions...
You didn't say why you are replacing the speedometer gear. Is it stripped? If the current gear was correct, then I would replace it for the same. The Ford parts counterman could tell you if there are differences in the gears. If you are stripping the teeth off the speedometer gear, the problem could be the drive in the transmission. A little work, but a easy fix.
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Speedometer gear questions...
This one is actually an exact replacement for what was in it before. It would appear that the gear is barely meshing with the drive gear in the T-case. It is wearing the very ends off of the plastic speedo gear which makes me think it may be the wrong gear. Is there actually a difference in gear diameter when changing the number of teeth? Sorry about all the questions, this is getting a little frustrating.
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Speedometer gear questions...
Ray , The number of teeth on the gear is the only variable , they are all the same diameter . If its chewing up the gear teeth you may have a problem with the gear on the output shaft that turns the speedo gear or a speedo cable binding a little . When you remove the speedo gear , you should be able to pull the cable out & check it for wear . It doesnt take much resistance to ruin the speedo gear . One other possibility may be contaminants , metal particles etc in the trans fluid in the transfer case may be helping to chew up the gear teeth .
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Speedometer gear questions...
Thanks Paul. I didn't think there could be any difference in diameter. With the gear pulled out, the cable does have some resistance. Is lubing the cable a possible solution? Does a speedo cable "wear out"? Any other suggestions as to what could cause resistance? Thanks again.
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Speedometer gear questions...
Does anyone know how many teeth are on a Yellow gear? I thought I had 18, but now i'm not sure. I need to add a tooth (to compensate for tire size) but my dealer has every color but Yellow.
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Speedometer gear questions...
[font size="1" color="#FF0000"]LAST EDITED ON 09-Feb-01 AT 10:04 AM (EST)[/font][p]I have a yellow gear in my truck, but I need one tooth more. I will count mine when I get a chance and post it. I added 32" tires and now the speedo reads low.
What color has one more tooth than yellow?
Wait a minute, maybe I need one less tooth. Somebody clear me on this. I went from stock tires to bigger tires.
BTW- in stock form I have an 88 f150 4x4 5speed with 3.55 rear.
Randy
What color has one more tooth than yellow?
Wait a minute, maybe I need one less tooth. Somebody clear me on this. I went from stock tires to bigger tires.
BTW- in stock form I have an 88 f150 4x4 5speed with 3.55 rear.
Randy
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Speedometer gear questions...
The cable will have some resistance , you really need to pull it out & have a look at it , it may have some frays or worn areas . Ive also seen the colder it is the more prone a worn cable is to causing problems .
As for the gear colors :
Gray = 17 teeth
Yellow = 18 teeth
Pink = 19 teeth
Blue = 20 teeth
Check with your local Ford Parts guy to be sure , but I think each tooth adds 2.5 Mph to the speedometer .
As for the gear colors :
Gray = 17 teeth
Yellow = 18 teeth
Pink = 19 teeth
Blue = 20 teeth
Check with your local Ford Parts guy to be sure , but I think each tooth adds 2.5 Mph to the speedometer .
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Speedometer gear questions...
[font size="1" color="#FF0000"]LAST EDITED ON 09-Feb-01 AT 11:36 AM (EST)[/font][p]RGAZ,
I have a 90 F-150 with the same setup as yours. I too went to a 32" tire, and my speedo is about 5 MPH off at 55-60. My local Ford parts guys said adding one tooth will add approximately 5mph at 60. So i'll be changing my stock yellow gear to the pink gear. Thankfully I wont need to change out the drive gear inside the tailhousing which is also yellow, not that it's a big hassle though.
I have a 90 F-150 with the same setup as yours. I too went to a 32" tire, and my speedo is about 5 MPH off at 55-60. My local Ford parts guys said adding one tooth will add approximately 5mph at 60. So i'll be changing my stock yellow gear to the pink gear. Thankfully I wont need to change out the drive gear inside the tailhousing which is also yellow, not that it's a big hassle though.
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Speedometer gear questions...
I have a 81 f100 with a 300i6 t18 4speed granny gear,331 rear gears,235/75/r15 tires, speedo does not reg at all.I have a white gear,my old one was damaged on the end of the teeth. FORD would not sell me one because they said it would be too hard to figure out to get the right one.Do they have different dia on the gears? I had to get one off a junker, a white one..Didnt work.Does anyone have any suggestions.THANKS IN ADVANCE.........
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Speedometer gear questions...
I went through 5 speedometer gears before I was told the drive gear on the input shaft was bad. Just pull the tailshaft off the transmission or transfer case and slip on a new one. I first noticed the problem when the cruise control started jerking. Then, I saw the speedometer needle jumping around. I would drive it around blind until I come up on the CSP speed traps. It was a little work, but an easy fix. Bigger tires turn slower due to the diameter, you'll need a smaller speedometer gear.
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Speedometer gear questions...
Ray, You can pull out the cable and lube it. There is a Lubriplate brand grease that works good on speedo cables. You can have some resistance if the cable is dry. Good luck.
Jakegypsum // Ford fleet, soup to nuts.
Jakegypsum // Ford fleet, soup to nuts.
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Speedometer gear questions...
Thanks for all of your help guys. Guess the next step is pulling the cable. No chance of being able to pull the cable from the bottom is there? If the cable isn't the problem, is it a huge job to change the gear in the T-case?
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Speedometer gear questions...
Ray , one way to check its operation is hook a cordless drill to the end of the cable & see how it feels & operates . You should feel any rough areas , also observe the needle & see how smoothly it operates .
What transfer case do you have ? BW 1356 ? Seems to me all you will have to do is remove the 4 Torx bolts that hold the extension on , remove it & the speedo drive gear will be visible , remove its retaining clip , slide the gear forward , remove the steel ball with a magnet that locks in place & slide the gear off . It will take you less than an hour . In fact I think its easier to check it before you fiddle with the cable .
What transfer case do you have ? BW 1356 ? Seems to me all you will have to do is remove the 4 Torx bolts that hold the extension on , remove it & the speedo drive gear will be visible , remove its retaining clip , slide the gear forward , remove the steel ball with a magnet that locks in place & slide the gear off . It will take you less than an hour . In fact I think its easier to check it before you fiddle with the cable .