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| | | | Joined: Nov 2015 Posts: 40 Wrench Fetcher | | Wrench Fetcher Joined: Nov 2015 Posts: 40 | Hi,
I have found a 3 speed with overdrive and floor shifter linkage which I am considering using for my 1940 1/2 ton. What do you think about this solution vs. S-10 transmission swap, differential gear swap or complete rear end swap? Are parts available for theses transmissions? Are there any sources for information such as gear ratios for theses? What problems might I encounter trying to make this swap?
Thanks,
John
| | | | | Joined: Jan 2001 Posts: 1,424 ODSS President | | ODSS President Joined: Jan 2001 Posts: 1,424 | Do you presently have torque tube or open driveshaft?
~ Cosmo
1949 Chevy Half Ton
Rocinante, like Don Quixote, he is awkward, past his prime, and engaged in a task beyond his capacities.
"...my good horse Rocinante, mine eternal and inseparable companion in all my journeys and courses." ...Don Quixote, Cervantes
"If you come to a fork in the road, take it."...Yogi Berra
"Rudeness is the weak man's imitation of strength." ...Eric Hoffer
| | | | | Joined: Nov 2015 Posts: 40 Wrench Fetcher | | Wrench Fetcher Joined: Nov 2015 Posts: 40 | | | | | | Joined: May 2001 Posts: 7,438 Extreme Gabster | | Extreme Gabster Joined: May 2001 Posts: 7,438 | You need to be more specific. A 3 speed with overdrive doesn't tell us much. | | | | | Joined: Nov 2015 Posts: 40 Wrench Fetcher | | Wrench Fetcher Joined: Nov 2015 Posts: 40 | I don't know much about it myself yet but I believe it is a Muncie out of a 1955-196? GM car. It has a solenoid operated overdrive. Casting number is 3837552. | | | | | Joined: May 2001 Posts: 7,438 Extreme Gabster | | Extreme Gabster Joined: May 2001 Posts: 7,438 | If so that is a great transmission choice. You will need an open drive rear end, preferably a 3.90 or 4.11. | | | | | Joined: Nov 2015 Posts: 40 Wrench Fetcher | | Wrench Fetcher Joined: Nov 2015 Posts: 40 | It might be a Saginaw. Did they all have the Borg Warner overdrive? Can the torque tube rear end be modified to an open drive or will I have to find one? | | | | | Joined: Feb 2001 Posts: 1,094 'Bolter | | 'Bolter Joined: Feb 2001 Posts: 1,094 | Look at the side cover, if it has 7 bolts it is a fully synchronized Saginaw. Good score. If the cover has 4 bolts it is a non- synchronized 1st gear, nothing wrong with that, it's what you have now. Both are Borg Warner overdrive units.
Tommy
59 apache 1/2t
261 short stepside
| | | | | Joined: Apr 2005 Posts: 2,098 'Bolter | | 'Bolter Joined: Apr 2005 Posts: 2,098 | I believe the bellhousing to transmission mounting locations were changed in 47 so it is unlikely this transmission will mount directly to your 40. It will require a different bellhousing or adaptor. In addition you will need to change the rear end just as you would with a T-5 or any other transmission designed to use with an open driveline. Other components used with the B/W overdrive include a pull cable, relay, kick down switch, and the wire loom, in addition to the solenoid and governor which hopefully came with the trans.
Fred
1956 3100 Pickup/Red/350/3sp OD/PS/Disc Brakes
1957 Bel Air Sport Coupe/Red/355/TH350/PS/Disc Brakes
2017 Silverado LT Single Cab SB/Black/5.3/6 Speed Trans
1947 Willys CJ2A w/F-Head engine
| | | | | Joined: Nov 2015 Posts: 40 Wrench Fetcher | | Wrench Fetcher Joined: Nov 2015 Posts: 40 | Thanks All, I have the non-sync version. I do have the solinoid and governor but not the kick down switch or relay. It looks like the relay might be the most difficult or expensive part to obtain. Can someone tell me what vehicle and year range will have a rear end with a 4.11 ratio and 6-bolt wheels so I can start that search? Thanks again! | | | | | Joined: May 2001 Posts: 7,438 Extreme Gabster | | Extreme Gabster Joined: May 2001 Posts: 7,438 | '55.1 to '59 have a 6 bolt 3.90. A Bosch type relay can be used as well as a DPDT toggle switch in lieu of the kick-down switch. Here's how I wired mine. | | | | | Joined: May 2006 Posts: 8,351 'Bolter | | 'Bolter Joined: May 2006 Posts: 8,351 | Another source for overdrive electrical parts Fifth Avenue Internet Garage
Bill Burmeister
| | | | | Joined: Dec 2000 Posts: 3,399 Gas Pumper | | Gas Pumper Joined: Dec 2000 Posts: 3,399 | | | | | | Joined: Nov 2015 Posts: 40 Wrench Fetcher | | Wrench Fetcher Joined: Nov 2015 Posts: 40 | Thanks Cletis,
Great information. Do you have a part number for the Bosch relay?
John | | | | | Joined: Nov 2015 Posts: 40 Wrench Fetcher | | Wrench Fetcher Joined: Nov 2015 Posts: 40 | Thanks Bill,
Its good to know I can get new parts!
John | | | | | Joined: Nov 2015 Posts: 40 Wrench Fetcher | | Wrench Fetcher Joined: Nov 2015 Posts: 40 | Thanks Deve,
That website is now in my favorites list.
John | | | | | Joined: May 2001 Posts: 7,438 Extreme Gabster | | Extreme Gabster Joined: May 2001 Posts: 7,438 | Thanks Cletis,
Great information. Do you have a part number for the Bosch relay?
John No part number needed. Just ask the parts guy for a 30 amp Bosch type relay with mounting tab. Any brand will do. | | |
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