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| | | | Joined: Oct 2009 Posts: 426 Shop Shark | | Shop Shark Joined: Oct 2009 Posts: 426 | Does anybody know how good of a build can be done to the saginaw 3speed tranny? Im puting a 396 in my 63 in the spring and want to keep the coloumn shift. How much hp and torque will this tranny take? Would I be better with a hd 3speed | | | | | Joined: Oct 2003 Posts: 5,152 Cruising in the Passing Lane | | Cruising in the Passing Lane Joined: Oct 2003 Posts: 5,152 | How are you going to drive it? How are you going to load it?
If used gently it may last a long time. If abused the HD 3-speed won't last either.
1955 1st GMC Suburban | 1954 GMC 250 trailer puller project | 1954 GMC 250 Hydra-Matic | 1954 Chevy 3100 . 1947 Chevy COE | and more...
It's true. I really don't do anything but browse the Internet looking for trouble... | | | | | Joined: Oct 2009 Posts: 426 Shop Shark | | Shop Shark Joined: Oct 2009 Posts: 426 | Just an everyday driver. I plan to build around 350-375hp engine running on pump gas. This will not be a race truck. Just want to be sure that I'm not going to rip the tranny out w/normal driving | | | | | Joined: Oct 2003 Posts: 5,152 Cruising in the Passing Lane | | Cruising in the Passing Lane Joined: Oct 2003 Posts: 5,152 | There are people running the Saginaw 4-speed behind 454's successfully, and since that 3-speed is basically the same design I'd expect normal driving would be fine.
Pulling a heavy trailer or drag racing would change my opinion and possibly your experience.
1955 1st GMC Suburban | 1954 GMC 250 trailer puller project | 1954 GMC 250 Hydra-Matic | 1954 Chevy 3100 . 1947 Chevy COE | and more...
It's true. I really don't do anything but browse the Internet looking for trouble... | | | | | Joined: Jan 2008 Posts: 69 Wrench Fetcher | | Wrench Fetcher Joined: Jan 2008 Posts: 69 | Are you sure you have a Saginaw? If first gear is not synchronized, then you probably have the Muncie SM318, although it is often referred to as a Saginaw. It's the most common transmission they used in the 6cyl cars and 1/2 ton trucks back then. It was available in the trucks until around 1967. As OldSub said it may last for years if driven easy, but they don't like abuse. I had a mild 327 in my first '65 pickup as a kid, and I busted several of them. But of course I was asking for it. Best of luck.
TruckNut
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| | | | | Joined: Oct 2009 Posts: 426 Shop Shark | | Shop Shark Joined: Oct 2009 Posts: 426 | 1st gear is not synchronized so its probably the muncie. I have the casting numbers somewhere. Would the saginaw be a better choice of trans? I want to retain the coloumn shift. I have the 12bolt truck reared w/3:73 gears | | | | | Joined: May 2006 Posts: 8,351 'Bolter | | 'Bolter Joined: May 2006 Posts: 8,351 | Here's a little food for thought, the SM318 was used behind 396s and even 427s as the standard equipment transmission in passenger cars. It also saw use behind Feullie 283s, Power-Pak 2x4bbl 283s, Feullie 327s, 348s, and even the 409. Driven normally, and not abused, it should be fine.
Bill Burmeister
| | | | | Joined: Jan 2008 Posts: 4,962 'Bolter | | 'Bolter Joined: Jan 2008 Posts: 4,962 | If your synchro gear and shift forks aren't worn like a lot of them are, with todays lubricants it should last a long time. | | |
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