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| | | Forums66 Topics128,050 Posts1,055,646 Members48,426 | | Most Online14,466 Apr 26th, 2026 | | AD Chevy Trucks Over 6,000 pictures Brad Allen has an awesome collection of Chevrolet factory pictures that he has set up from film strips. Check them out!
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on the Internet for over 30 years! and not clogged down with Ads! Again, thanks! | | | | Joined: Jun 2010 Posts: 215 Shop Shark | | Shop Shark Joined: Jun 2010 Posts: 215 | I spoke with an older gentleman last night about a 235 he has for sale, he tells me it has a Monza four speed bolted to it. I asked him if it needed an adaptor plate to connect, and he told me no, its a straight bolt on change. Has anyone ever heard fo this ? I don't know the year of the engine but am going to look at it on the weekend.
| | | | | Joined: Nov 2008 Posts: 64 Wrench Fetcher | | Wrench Fetcher Joined: Nov 2008 Posts: 64 | I think Monza used the saginaw 4 speed just like the vega did , they also used them in a lot of other cars also. it should be a direct bolt up . | | | | | Joined: Apr 2005 Posts: 926 Shop Shark | | Shop Shark Joined: Apr 2005 Posts: 926 | The Saginaw 4 speed was popular in the early to mid sixties Chevy full sized cars-Impala and such. Good transmissions;bolt right up to the 3 speed bellhousings,same clutch splines,and there's an adapter kit available to hook one up to a Torque-Tube drive. I've also heard rumors of using the overdrive output shaft and tailshaft housing,to give you a 4 speed with overdrive. that'd be the best of both worlds! Speed | | | | | Joined: Jun 2010 Posts: 215 Shop Shark | | Shop Shark Joined: Jun 2010 Posts: 215 | Do you know who carries the adaptor setup to connect this to the '46 torque tube driveline ? Is the overdrive unit a saginaw part ? Or should I be looking for something else?
| | | | | Joined: Jun 2010 Posts: 215 Shop Shark | | Shop Shark Joined: Jun 2010 Posts: 215 | I guess I should have also added, the same guy has a complete '55 chassis that I could use the drivetrain out of too, would this be an even better option ? Is the rear end the same width or is it not useable. Thanks for all the great advice! AM | | | | | Joined: Nov 2005 Posts: 6,100 'Bolter | | 'Bolter Joined: Nov 2005 Posts: 6,100 | Hy andy46, there are actually two totally different 55 chassis, the parts from a 55.1 or "A" would be easier to adapt than those of a 55.2 or "B" series, hope that helps. | | | | | Joined: Jun 2010 Posts: 215 Shop Shark | | Shop Shark Joined: Jun 2010 Posts: 215 | I think this is actually the second series chassis, but not 100% sure, but thats a good question, going to have to phone the guy now and find that out. Thanks Andy | | | | | Joined: Dec 2004 Posts: 1,897 Shop Shark | | Shop Shark Joined: Dec 2004 Posts: 1,897 | Andy, You will find your choices are really limited if you are keeping the torque tube driveline. A call to Patrick's in Arizona is a must. I believe he has a kit for using the saginaw 4 speed with the torque tube. However, the 1946 has a different bellhousing bolt pattern than the later trucks. The deco and prewar trucks had 3 extra holes drilled in the bellhousing for the brake and clutch pedals. A later 47-54 bellhousing will bolt to the saginaw transmission, and your crossmember with no modifications, but it will not bolt to your brake and clutch pedals. I believe Jim Carter sells an adapted bellhousing for this purpose... to put a later transmission in an earlier truck and bolt the brake and clutch pedals back to the bellhousing like stock.
John | | | | | Joined: Jun 2010 Posts: 215 Shop Shark | | Shop Shark Joined: Jun 2010 Posts: 215 | Thanks for the advice guys, I should have stated earlier, the 46 truck I have already has a '54 motor in it now. So I'm thinking of swapping in a '55 motor with the Monza Saginaw four speed and maybe using the open rear end from the donor chassis if I get that too. Or sticking with the closed 46 driveline. Not sure which route to go with. Andy
| | | | | Joined: Dec 2004 Posts: 1,897 Shop Shark | | Shop Shark Joined: Dec 2004 Posts: 1,897 | The bellhousings are interchangeable to the motors. Any 1937-1959 216, 235, or 261 chevy bellhousing will bolt up to any 1937-1959 chevy motor. The same is true with gmc motors and bellhousings from 1939-1959. In fact, the gmc bellhousings are interchangeable with the chevy bellhousings.
The trick is to use the bellhousing that fits your chasis the best. In your case it will probably be the 1937-1946 bellhousing on the 1955 motor. This will allow you to run the stock transmission and torque tube behind the newer engine.
If you want to change transmissions you have a few options.
1. Use an adapter plate between the bellhousing and transmission. This works extremely well when putting a T5 behind a stovebolt with the early 1937-1946 bellhousing. 2. Get a modified 1947-1954 bellhousing. Ok, it might actually be 1948 or 1949 and later to have the correct bolt pattern for a muncie or saginaw 4 speed. The 1947-1954 bellhousings will bolt into a 1946 frame with the 1946 rear motor mounts and crossmember. These bellhousings will not bolt to the clutch and brake pedals... unless they are modified. 3. There are many other options but they all require more fabrication. | | | | | Joined: Nov 2001 Posts: 1,517 'Bolter | | 'Bolter Joined: Nov 2001 Posts: 1,517 | Anybody got more info on the closed drive adapter for the rear of the Saginaw 4spd trans? Is that a Patricks deal. Or something to look for at a swapmeet or junkyard? Thanx for the help,,,,,,,, | | | | | Joined: Dec 2004 Posts: 1,897 Shop Shark | | Shop Shark Joined: Dec 2004 Posts: 1,897 | Marty, I believe that's a Patrick's deal.
| | | | | Joined: Jun 2010 Posts: 215 Shop Shark | | Shop Shark Joined: Jun 2010 Posts: 215 | Thanks for all the info on this, good stuff, now just need to pick a route, and I'll be on my way! Thanks again!
| | | | | Joined: Nov 2001 Posts: 1,517 'Bolter | | 'Bolter Joined: Nov 2001 Posts: 1,517 | Thanx Bigdaddy, Ill check out Patricks. Happy Truckin. | | | | | Joined: Jun 2010 Posts: 215 Shop Shark | | Shop Shark Joined: Jun 2010 Posts: 215 | I did buy the engine and the trans, but still not sure I'm going to go that route. As an aside the rolling chassis he has is for the later '55 pickups, and is a complete chassis with a 235 and trans in it, If anyone wants it, he wants $200. for it complete, a pretty decent deal for a complete rolling chassis. If anyone wants it PM me, and I'll give you his number. Thanks guys. | | |
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