3 speed transmission w/overdrive

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nzkiwi
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Joined: Fri Nov 30, 2018 2:31 pm

3 speed transmission w/overdrive

Post by nzkiwi » Mon Dec 02, 2019 4:05 pm

I just read an article in The Early Bird magazine for November/December 2019 on page 36 on the question/answer page. Someone had a question on the 3 speed with overdrive and Gil Baumgartner responded with a response that kind of floored me. He stated that "Only approximately one percent of all 1957 Thunderbirds had an overdrive transmission." I find this to be unbelievable but certainly respect Gills knowledge on early birds.

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Florida_Phil
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Re: 3 speed transmission w/overdrive

Post by Florida_Phil » Tue Dec 03, 2019 10:54 am

Most of the early TBirds I see have automatic transmissions. A friend has a 57 with a three speed manual transmission without O/D. It took me a long time to find a nice rust free manual transmission TBird. My '55 came with a three speed manual with O/D. I had never driven an O/D car before I purchased this one. O/D was years ahead of it's time. My 55 has a 4.11 gear and a modified 301 cu. in. 292. It's a rocket in first and second. At 60 miles an hour in third O/D, I'm doing a little over 2,000 rpm. The only bad thing about O/D is you must remove the engine to work on the transmission. There is no way to drop the transmission with the engine on the mounts. The shop manual says you can do this by removing the bell housing. Good luck with that.

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ranchbird
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Re: 3 speed transmission w/overdrive

Post by ranchbird » Wed Dec 04, 2019 7:24 pm

I'm going to get my 56 in the air and check out the situation in regards to removing the 3spd. od to replace the clutch, or if I can move it enough to remove the bell housing to get at the clutch. I really don't want to pull the motor out, I've got different answers yes you can, no you cant depends on who you talk to , will see.

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Alan H. Tast
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Re: 3 speed transmission w/overdrive

Post by Alan H. Tast » Wed Dec 04, 2019 7:56 pm

nzkiwi wrote:
Mon Dec 02, 2019 4:05 pm
I just read an article in The Early Bird magazine for November/December 2019 on page 36 on the question/answer page. Someone had a question on the 3 speed with overdrive and Gil Baumgartner responded with a response that kind of floored me. He stated that "Only approximately one percent of all 1957 Thunderbirds had an overdrive transmission." I find this to be unbelievable but certainly respect Gills knowledge on early birds.
That statistic held true through the 1950s - 1958-1960 T-birds had 1% with just a standard 3-on-the-tree, and another 1% with OD. As for '55s and '56s the percentages with manual transmissions may be a little higher, but it's been ages since I've needed to reference that statistic.
Alan H. Tast, AIA
Technical Director/Past President,
Vintage Thunderbird Club Int'l.
Author, "Thunderbird 1955-1966" & "Thunderbird 50 Years"
1963 Hardtop & 1963 Sports Roadster

voltron
Posts: 52
Joined: Thu May 10, 2018 6:06 am

Re: 3 speed transmission w/overdrive

Post by voltron » Wed Dec 04, 2019 11:28 pm

ranchbird wrote:
Wed Dec 04, 2019 7:24 pm
I'm going to get my 56 in the air and check out the situation in regards to removing the 3spd. od to replace the clutch, or if I can move it enough to remove the bell housing to get at the clutch. I really don't want to pull the motor out, I've got different answers yes you can, no you cant depends on who you talk to , will see.
The '56 has a removable cross member where as the '57 doesn't which makes removing the o/d trans very difficult if not impossible. You may not have too much trouble with your '56.

ranchbird
Posts: 54
Joined: Sun May 11, 2014 10:53 pm

Re: 3 speed transmission w/overdrive

Post by ranchbird » Wed Dec 04, 2019 11:42 pm

So I read through the 56 shop manual on changing the clutch, if I'm understanding it correctly you unbolt the tranny and the tranny cross member slide it back as far as you can then remove the inspection plate on the bottom of the bell housing then remove the fork and throw out bearing then the clutch and pressure plate and drop them out through the bottom of the bell housing. If you need to remove the tranny you unbolt the bell housing and rotate 180 degrees (upside down) and let it down between the input shaft and flywheel then remove the tranny.If you go this far, to reinstall you put the bell housing back on then the throw out bearing clutch etc. through the bottom opening of the bell housing, sounds like it should work. I guess the main objective is to slide the tranny far enough back to be able to slide the pressure plate down between the end of the input shaft and the flywheel and out the bottom of the bell housing.

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