Speedometer gear T-98
 

Do to a little bit of confusion at least on my part and then the next thing was what a guy would call the gears then things can get a little frustrating. The driven gear is what is showing in my picture but have seen guys say drive gear and that is the one inside it. The picture of the trans I am posting is not one found in our trucks but at least it shows the gears and where they are located and the name. Maybe it will help someone so he or she will ask for the correct part.


I did find a post like in 08 on here and with it being so old I figured it is best to make a new post.


I thought I had found a new one so ordered it and was like for the correct years but for Dodge/Jeep so looks like they didn't use as heavy duty 4 speed as this one.
Here is what I had ordered and we had put the old one back in and didn't count the teeth :-X17 but the old one is a 20 tooth and the OD of the gear is 7/8 and the one I bought might be 5/8?
Crown Automotive - Speedometer Drive Gear - Fits 1954 to 1964 Sedan Delivery and Station Wagon - 4WheelParts.com


The old one from what we can see is the end of it is like broke off and even though you can get the cable in it then it will not stay. Even if you have one that you do not want to part with then a picture would be nice and might just take the new one and cut the end off and weld it on the old? But would need a overall measurement to get that correct.


The number on the gear is O1T-71 and then G-20 or could be a C?


Any help would be great or sure and here is a picture of the new one on the left and old one right. Yep should have turned it around so you could see the other end that seems to be missing a piece best we can tell because it was to rough to be factory.


This trans was installed in my friends 56 panel and it came with the normal 3 speed but it works fine so he is going to just keep it that way for now. Guess is it came out of the larger trucks from back in the day. Once we can get the correct part then we will see how far it is off and go from there. Something is better than nothing.


What you got guys???

Numbers Dummy had this to say
 

O1T-17271-A / 18T Speedo Gear

How far off would you say the speedo is? And is it fast or slow?

These driven gears only came with 18-19-20-21-22 teeth. So if a 17T is needed, I'lll have to figure out a drive gear instead.

Bad news, all these gears are obsolete, but I may be able to find new ones.

btw: 1965 F250 / 352 / C-O-M / Dana 60 / 4.56-1 / 7.00 x 16 tires = O1T-17271-A :)


This all I had to go buy when I thought I found the one I bought but it will not work at all.

The T9 has the same gears. I switched mine when I converted to a T98. The driven gear has to work with the drive gear you have just to be clear.

There is a chart that was up one time that showed all the combinations. Maybe someone will post it up again.

I kind of had/have a similar problem but not a t-98 trans the comparisons in my post are the MH specific gear and the speedo gear from a 48 52 t9 4 speed spur gear trans.

https://www.ford-trucks.com/forums/1...or-mh-4x4.html

Anyway,

Im; not familiar with the parts numbers of these trans but im planning on putting a t98 from a 51 52 f6 in my f2 MH so kind of ties this together.

am I reading your post correctly that the t-98 trans you have is from a 1953 to 1955? I think the ford T-98 units changed again for 56??

I have a T-98 from a 53 truck all in parts and pieces the case was cracked, I may have a stock speedo gear? I can take a look if that sounds like the correct era

Josh

Sorry, I should have been more specific. I swapped gears back and forth on an early T98. A 1950 T98 out of a F6 and my F3 T9.

I don't know about the early vs late models. Hopefully Josh can fix you up with the right parts.

Scott

12 available NOS .. If this is the DRIVEN gear you want, I'll post the sources.

01T part number prefix dates back to 1940 truck, these gears were used for 30+ years in all sorts of applications, including 1968/72 F100/350 360/390 C6.

Would be great if you do have one.


I think I am under standing what I have read and you just can't change the speedo gear that the cable connect to a diff tooth one without changing the main drive gear inside the tranny.

I do remember changing the nylon type on something years ago.


Somewhere in my shop I have one or maybe two of the units that were made up to correct the speedo and if I can find it then if lucky it might help a little getting my friends to read a little better and not so for off.

Someone here posted a chart for me with the speedo gear combinations. I think there are only 3 drive gears and each worked with maybe three different driven gears. You had to have the right ones to work together. I'll see if I can find it in my older posts.

That's incorrect, there are only two possible DRIVE gears (7 & 8 teeth) for your application, to go along with the 18-19-20-21-22 tooth DRIVEN gears.

Did you see post #6?

Bill, do you know a source for the 8 tooth gear?

Scott

What's the application?

For my 1950 T98

Need more info than this, what is the seriers (F3?), axle ratio and tire size (if P-metric, don't bother), just tell me if the wheels are 15, 16, 17 or whatever.

I have the T98 in my F3. Came out of a 50 F6. I have a 3.73 gear and 6.50-16 tire. My driven gear has 21 teeth.

The chart the Ross posted in my link above shows the 8 tooth gear to be 01Y 17285-B so I thought that would be the one I needed. If it is, where can I get one?

Scott