5.17:1 Worm Gears - who wants them?

[Neil Wilson]

Hello AA'ers with '28/'29 worm drive rear axles,

I am working with a shop (via e-mail) which is currently making the 5.17:1 worm gear set for the TT. They are willing to modify the worm input shaft to the AA specification so that the AA worm shaft to drive shaft coupler fits. Consequently, the worm along with the TT worm gear (that they currently manufacture) will work for the AA axle.

The shop wants some firm orders to proceed with this project. Soooo, who is interested in this gear set which will sell for less than $700?

The shop also says that their worm gear currently works with an original worm and they are currently available for $375.

Note that the TT worm gear is about 1/4" smaller in width than the AA worm gear (see picture). But, otherwise, it will bolt into the AA axle and work great. Ford made this gear wither for the AA because they went from a 1 ton TT to a 1-1/2 ton AA.

[Roy Williams]

Hey Neil, I missed your post here. I would like to order at least one set. Are the sets being produced now correct for the TT but will work in the AA? I'm holding the high speed gears I found for my AA and waiting to find the spedometer gears before installing. i"m presently rebuilding a 1924 express and I'm unsure of what it has but I plan on holding these trucks awhile and would gladly support this cause. any leads on the AA speedometer gears would be appriciated as well. How many orders do you need and how many have been placed. Let me know how this develops. Thanks, Roy

[Neil Wilson]

Hello Roy,
You are the first to respond to this ad. My understanding is that the TT gears are currently available. The TT worm gear (large gear) works in an AA also. It is 1/4" smaller in width of the teeth but otherwise is the same. The TT worm is the same as the AA except for the splines on the input shaft (which are smaller for the TT). The shop would need to invest in tooling to machine the splines to match the AA. That is why they want to have some orders before they invest in the additional tooling. I don't know how may order the shop wants before making the investment.

You can contact the shop at machshop@arkwest.com if you want. I did mention the corresponding speedometer gears to them. I think that they were headed to a swap meet where they were going to display/sell the TT gears.

Note that I have a set of the high speed gears to sell for $650 plus crating & shipping. The worm gear looks to be NOS and is a TT. The driving worm is in excellent condition.

[spectria]

Hi Neil,

I can't afford the gears, and I don't even know if I need them, but I want to say something to you...

Thank you for always being there and trying to find ways to keep this alive.

I really appreciate your efforts.

Someday I hope to be able to afford to get all the things I need to get my Trucks right.

Thanks again.

[elfox]

Neil -

I know it has been a while since this post was put up, but has anything materialized on this? With the difficulty of finding a good set of original 5.14 gears, this is very appealing if it can be done.

Thanks,

Elfox

[Neil Wilson]

I got only one responses from anyone wanting to spend $'s. The shop would have initial tooling costs. So, it would take several customers committed with $'s before they would consider making the gears for the AA.

I have not done anything further since I don't need any of these gears for my projects.

[Bob C]

Neil, could the AA drive shaft be resplined to to fit the TT gear?

Bob

[Neil Wilson]

The TT input shaft has a smaller diameter than the AA. There is a splined collar which joins the drive shaft with the worm input shaft. I had thought that a collar could be made to fit the AA drive shaft on one end and the TT worm input shaft. Does anyone have an idea on that?

[Bob C]

Neil, do you know how many splines and what size they are on the TT
worm and the TT drive shaft?

Bob

[Neil Wilson]

Bob,
Below is a picture of the TT worm input shaft. I am guessing that it has six splines. I don't have a photo of the TT drive shaft or the coupler.

[Reds34]

Neil,
This may be a silly question, but how would you tell the difference between the two different gear ratios in the worm drive rear ends? Do you still divide the number of teeth? I've never really seen a worm drive rear end apart up close.

Red

[Neil Wilson]

The gear ratio is determined by dividing the number of teeth on the worm into the number of teeth on the worm gear. As I recall (6/31 = 5-1/6:1 and 4/29 = 7-1/4:1)

[Reds34]

Ok. I wasn't sure how easy it was to count the the teeth on the worm.

Red