Hot Rods 3Speed ovedrdrive ID help please

Hi there thanks for letting me post. I have a 1957 chevrolet pickup with a 235CID engine along with a 3Speed column with overdrive. The tail of the transmission is showing R10K-1 W.G.DIV. Can anyone help me identify this transmission and what is the correct Tooth Driven Gear it should have. How many teeth etc. (the gear was missing when I picked it up from a shop that since closed down) The gear housing measures ~ 1 3/4" tall. I have attached photos. I checked a non overdrive transmission laying around so I took off the housing and gear from that one to compare. The gear housing is longer. so it is obviously different. When installing the gear it will obviously mate with a gear inside the tail. Will it spin freely when I install a new gear or will it slip in and not turn until it is in use? Just want to know what to expect. I purchased a Dakota Digital instrument cluster and noticed it the missing gear when installing the electrical sending unit on . No wonder my speedo was not working & I was leaking from there.

 

Its a Borg Warner, they were used on many different brands with just a different bolt pattern, or output shaft. So, once you figger out what gear, it may not necessarily be from a chevy. Sorry, no gear info...good luck

 

from this page

https://chevy.oldcarmanualproject.com/1929_57chevyparts/index.htm

we look up illustrations, and find



that group 4.338 is where we need to look.

then



we find that it's a different gear than normal transmissions, and takes gear 3708143.

googling that, we find Summit lists them but they are on serious back order.

https://www.summitracing.com/parts/oer-3708143

So, search for a used or NOS one.

https://www.ebay.com/itm/364094931908

 

man...chapter AND verse from jim that early--nice!

 

You have a Muncie 319, that is the Overdrive version. The Driven gears come in different colors which signify different numbers of gear teeth as shown in the chart above.






The three to the right are for the Muncie transmission, the four from the left are for the Saginaw transmission. Note the difference in tooth count and diameter. Changing tire size will affect speedometer accuracy, you can get a more accurate speed by changing out the Driven Gear.

 

While their main focus is Fords, Van Pelt Sales has a great knowledge of the R-10 and R-11 overdrives. Might be worth a call to Mac, looking for the interchange Rusty referred to above.

http://www.vanpeltsales.com/

 

Thank you for the response.!

 

Wow thanks for the help this is great information exactly the feedback I was hoping for. This site is great!