New Speedometer Drive Worn out in 60 miles?
 

Has anyone else had a new speedometer drive wear out right away? This is a 18 tooth drive, I bought it as a complete unit from a reputable supplier. Car is a new build, late 1932 torque tube. Is there something wrong in my setup or is this a repo parts problem. It worked very well at first, but died after 60 miles. I likely have some metal fillings in the torque tube now.

Re: New Speedometer Drive Worn out in 60 miles?
 

Looks like it wasn’t meshing fully.
I just put a 18 tooth in place of a 19 the 2 housings had a different centerline for the shaft.
I think the gear is nylon on the reproduction ones

Re: New Speedometer Drive Worn out in 60 miles?
 

This one was a steel gear. Came as a full unit.

Re: New Speedometer Drive Worn out in 60 miles?
 

The turtle shaft hight changes with different size gears, (ratio) So, if someone put the wrong gear in a turtle it would not mesh correctly. A possibility.

Re: New Speedometer Drive Worn out in 60 miles?
 

https://www.fordbarn.com/forum/attac...9&d=1748492668

https://www.fordbarn.com/forum/attac...0&d=1748492668

https://www.fordbarn.com/forum/attac...1&d=1748492668

Re: New Speedometer Drive Worn out in 60 miles?
 

I think this is the case too. What is the number on the outside of the turtle? How many teeth in the worn unit?

Re: New Speedometer Drive Worn out in 60 miles?
 

This is a reproduction unit with no numbers. It came as is, ready to run. So it likely a faulty part and not something in the driveshaft set up?

Re: New Speedometer Drive Worn out in 60 miles?
 

With the turtle off, look at the teeth on the driveshaft gear which is easily viewed. This recent thread has some pictures and guidance.

https://www.fordbarn.com/forum/showt...ghlight=turtle

Re: New Speedometer Drive Worn out in 60 miles?
 

Everything looks really good besides the turtle. I installed a 19 tooth original that a friend gave me. Will see how it does. If anyone has an original 17 or 18 tooth please let me know.
Thanks

Re: New Speedometer Drive Worn out in 60 miles?
 

The turtle will take a one tooth change without modification. For two tooth difference, buy another turtle or grind to fit or by adding gaskets between the turtle and the torque tube.

Do you know the rear-end gearing? See this post to pick the correct tooth count in the turtle.

https://www.fordbarn.com/forum/showp...12&postcount=7

Re: New Speedometer Drive Worn out in 60 miles?
 

I have 3.54 gears with 7.50x16 tires. I am going to try to stick with a complete and original turtle.

Re: New Speedometer Drive Worn out in 60 miles?
 

i may have to replace my turtle due to stripped threads...so this thread interests me.

so can i assume that if i replace my turtle with a new turtle with the same tooth count, i will, most likely, not experience the problems outlined by the owner of this thread?

the only reason i ask, is that if the answer is "yes", then i need to remove the old turtle and count its teeth before ordering a new one.

Re: New Speedometer Drive Worn out in 60 miles?
 

Yes, if the damaged one reads correctly. I would definitely count the teeth since they may have been changed out.

Re: New Speedometer Drive Worn out in 60 miles?
 

striped threads on the torque tube?

Re: New Speedometer Drive Worn out in 60 miles?
 

the speedometer cable has knurled nuts that screw on to male threads at each end. one of the nuts threads on to the dashboard's speedometer gauge, the other nut to what is being, i think, referred to in this thread as "the turtle".

i was referring to the male threads on the turtle as being stripped, although cross-threaded would probably be more accurate. i won't be certain unless and until i get it off and have a closer look at them.

Re: New Speedometer Drive Worn out in 60 miles?
 

I paid $85 for the aftermarket drive. I am only buying a Ford one next time.

Re: New Speedometer Drive Worn out in 60 miles?
 

Here is an "Gennie" 18 on ebay right now


#176979558589

Re: New Speedometer Drive Worn out in 60 miles?
 

here's a few pics of the one i just removed from my new-to-me 1941 deluxe.

as you can see the damaged connector and stripped threads, as i imagined, were what was preventing me from threading the speedometer cable back on the other day. i'll be needing a new one. and because the old one is labeled "18" on top, i'll be ordering an 18 tooth one from here: https://thirdgenauto.com/product/new...ly-3-54-ratio/

Re: New Speedometer Drive Worn out in 60 miles?
 

https://www.fordbarn.com/forum/attac...2&d=1748979894

https://www.fordbarn.com/forum/attac...3&d=1748979940

https://www.fordbarn.com/forum/attac...5&d=1748979995

Re: New Speedometer Drive Worn out in 60 miles?
 

Count the teeth before you buy.

Re: New Speedometer Drive Worn out in 60 miles?
 

I would fix the thread before buying a new one. If you do buy a new one report back if it works for more than 60 miles.

Re: New Speedometer Drive Worn out in 60 miles?
 

i removed the old speedometer cable today, but had to cut it in half to get it out as neither end fitted through the hole in the fire wall along with the wiring harness.

the task is now at a standstill as i contemplate drilling a hole near the bottom driver's side of the footwell just for the speedometer cable. i really wish there was another way...but am not seeing it. :(

Re: New Speedometer Drive Worn out in 60 miles?
 

i don't think that's possible, or at least with what i have to work with anyway. the pictures don't really reflect how bad the threads are on the housing and i didn't mention that the end plate is buckled too.

i will say though, that it looks like the gear assembly might be removable from the housing (i've seen the housings for sale sans gear) on these units, but i would venture to guess that the one that failed a 60 miles involved some sort of mismatch of parts.

Re: New Speedometer Drive Worn out in 60 miles?
 

The failed one came from where you are looking to buy a new one

Re: New Speedometer Drive Worn out in 60 miles?
 

did the one you bought NOT have the same number of teeth on the gear that was cast into the housing? if so, that's not good!

Re: New Speedometer Drive Worn out in 60 miles?
 

The repos don’t have any numbers

Re: New Speedometer Drive Worn out in 60 miles?
 

i bought mine from here: https://thirdgenauto.com/product/new...ly-3-54-ratio/

and the picture accompanying the product show an "18" cast into the housing.

Re: New Speedometer Drive Worn out in 60 miles?
 

The number on the turtle represents the number of teeth on the turtle’s gear, specific to the differential ratio, NOT specific to any particular year. Wheel and tire size is a different ball game. Know your final drive ratio before laying out your money.

Re: New Speedometer Drive Worn out in 60 miles?
 

Find an original, it's not like they are super rare.

Re: New Speedometer Drive Worn out in 60 miles?
 

Barnfind 08 on here had them N.O.S.

Re: New Speedometer Drive Worn out in 60 miles?
 

received the speedometer mount today and as predicted by "Duke" there are no numbers on the casting and i'm more than a little upset in that the one pictured in the ad clearly shows the "18" on it.

they'll be hearing from me!

Re: New Speedometer Drive Worn out in 60 miles?
 

You were cautioned that it was not original. It is in fact advertised with the word "NEW" all in caps in four places. Proof of the pudding is how long it will last. Ask Mike if he can warranty it, given the hefty price it commands. Keep in mind that Mike is not the enemy, he's trying to make do with what's available.

Re: New Speedometer Drive Worn out in 60 miles?
 

Check out the price now !
https://www.ebay.com/itm/353320434907

Re: New Speedometer Drive Worn out in 60 miles?
 

https://i.ebayimg.com/images/g/TuAAA...RMZ/s-l500.jpg


1932-48 Ford NEW 18 tooth speedometer drive gear assembly (3.54 ratio) 40-17270
Opens in a new window or tabBrand New
$103.75
Buy It Now
+$8.35 delivery
18 sold

Re: New Speedometer Drive Worn out in 60 miles?
 

One thing missing that I thought I'd add is how smooth does the cable core and speedometer shaft turn? If they both turn easy with no binding then disregard. I think the driver gears were 13-tooth but it's hard to tell with helical gears. Everything has to be in good shape to insure reliable function. I'm sure the OP is familiar with the speedometer gear chart in the green bible parts book. That's the way to go for proper speedo gearing with rear axle and tire sizes. Just my 2 cents.

Re: New Speedometer Drive Worn out in 60 miles?
 

okay, here's the final story on my new speedometer mount...

short answer...i'm not using it!

why? because when i went to count the number of teeth, the rotor hung up about half way around. and after i forced it around using my thumb it was still not rotating freely. there was a bit of red (locktite?) and rust(!) on the shaft. even after "working it" for five minutes, it was still not moving freely. so i decided to take another look at the original OEM mount that i had removed the other day and that had questionable threads (see previous post). and decided to use it instead. all in all it was the better option.

BTW, the mount pictured in the ad on the website where i purchased the new mount was NOT the one that was delivered. to me, that's tantamount to buying an original vintage car pictured in an ad, and being delivered a replicar. their website will now serve as the very last resort for parts.

Re: New Speedometer Drive Worn out in 60 miles?
 

Be aware that this site is as much a Well-functioning community as well as an online forum. One should be careful about using rash language about members of this site, whether individual or corporate. It is not only impolite, but can sometimes lead to unexpected, negative results.

Research the situation before spouting off.

Re: New Speedometer Drive Worn out in 60 miles?
 

i trust that being called, "impolite" and "spouting off" and "to be careful about using rash language" is not your common response to a measured post concerning "truth in advertising" and quality of a product on a website.

i'll let you have the last word as i will not respond further.

Re: New Speedometer Drive Worn out in 60 miles?