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| | | Forums66 Topics128,191 Posts1,057,364 Members48,469 | | 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: Oct 2011 Posts: 206 Shop Shark | | Shop Shark Joined: Oct 2011 Posts: 206 | So I wanna get rid of my torque tube and tranny and I found a 1957 rear with 3.36 gears. Im thinking I can use this rear end with a stock 56/later 4 speed and then when I come across a 3 speed over drive I can just swap those out. WIll this work?
Will the 3.36 be high enuf to drive on the high way with out overdrive?
Will I need a new drive shaft when I switch from the stock tranny to a od tranny?
Did chevy passenger cars have 16' 5 lug steel wheels at all, or would I have to get new steel wheels for the back, (I just bought 16" tires all around so I dont want to go to 15 wheels.)
Thanks again for you help | | | | | Joined: Jan 2001 Posts: 5,337 'Bolter | | 'Bolter Joined: Jan 2001 Posts: 5,337 | 3.36 is good for highway driving. OD transmissions are the same length as most three and four speed transmissions. There were no stock 16" 5 lug Chev wheels.
See the USA in your vintage Chevrolet! My Blog | | | | | Joined: Oct 2011 Posts: 206 Shop Shark | | Shop Shark Joined: Oct 2011 Posts: 206 | thanks so I wont have to change drive shaft twice but I need to order new rims from coker? | | | | | Joined: May 2001 Posts: 7,438 Extreme Gabster | | Extreme Gabster Joined: May 2001 Posts: 7,438 | If you are referring to an SM420, it takes a different driveshaft than a 3 speed. | | | | | Joined: Oct 2011 Posts: 206 Shop Shark | | Shop Shark Joined: Oct 2011 Posts: 206 | I was thinking a saginaw, sm420 is later right? and can 1957 chevy passenger hubs be drilled for the trucks 6 lugs? | | | | | Joined: Apr 2005 Posts: 2,102 'Bolter | | 'Bolter Joined: Apr 2005 Posts: 2,102 | SM420 is a truck 4 speed. First gear is called a granny gear. This is probably not what you want for this conversion. You could use 51-54 passenger car front hubs. Then you would have the same bolt pattern all around. As far as drilling the pass car axles for 6 lug, there may not be enough surface area to match up with the bolt pattern. I had my stock 56 truck axles redrilled to match the 5 lug disc brake conversion and it works fine. You probably don't need an OD with a 336 rear end 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: Dec 2003 Posts: 2,733 Shop Shark | | Shop Shark Joined: Dec 2003 Posts: 2,733 | IMO a 3:36 is too high for a 216 if thats what you have in the Burb. 57' cars were originally equipped with 3:36 for V8 A/T and even V8 3 speeds were 3:55 or 3:70 in tri-fives and 6 cylinders were 3:70-4:11 range so that's why I doubt it's low enough for your application.
You don't say what engine you have so maybe you've already researched this and understand what is correct. | | | | | Joined: Oct 2011 Posts: 206 Shop Shark | | Shop Shark Joined: Oct 2011 Posts: 206 | sorry, I have a 58-62 235. I want to be able to fly and wont ever haul anything bu a standup bass rig.
I think I will pick up a 3 speed out of a 68 truck I saw on craigs.
So I wont need a overdrive with this then correct? I mean I should be able to drive 50 miles at 60 miles a hour?
Im just gonna get some series 12 wheels for the back.
It looks like my 57 passenger rear has the pads on the bottem. Do I need to relocate then, I mean It looks like the pads are in the same place on my 53 torque tube rear.???
You guys rock, I am grateful to everyone.. | | | | | Joined: Apr 2005 Posts: 2,832 'Bolter | | 'Bolter Joined: Apr 2005 Posts: 2,832 | A 235 with a 3.36 rear can run all day long at 60mph. A 3.36 with an OD would give a 2.35 final drive. A healthy V8 would strain pulling those gears up hills or into a strong headwind.
Evan
| | | | | Joined: Aug 2011 Posts: 835 Shop Shark | | Shop Shark Joined: Aug 2011 Posts: 835 | I can run 60 mph all day long in my '51 burb with the stock rear end, torque tube and '53 235 powerglide engine. Been doing this since I got the truck in 1973.
I would save yourself a whole lot of trouble and just go with what you have. Alternatively you could get the higher ratio gear set from Patrick's for your rear end, and then you could cruise at 65 or 70. Still a whole lot less trouble, and you keep your truck original.
All I carry most of the time is my fiddle, mandolin and tenor banjo.
Kurt | | | | | Joined: Oct 2011 Posts: 206 Shop Shark | | Shop Shark Joined: Oct 2011 Posts: 206 | I already got the rear end. How can you do highway speeds for any length? I tryed once and the temp went up, oil pressure dropped and engine stalled. So I read some where on a list of what rear ends that I'd have to relocate the perches to the top but I'm thinking that's for. 55 n up because the springs ride under the axel now and that's how a 57 cars set up as well?? | | | | | Joined: Aug 2011 Posts: 835 Shop Shark | | Shop Shark Joined: Aug 2011 Posts: 835 | Do you have a 1/2 ton? If so, it should not be a problem to run 60 with a 235 high pressure engine, although 55 is a sweeter spot. Could be that you have an engine or radiator problem. Best to investigate that possibility before you dive into a major redo. Here is an image of the gear set that Patrick sells that ought to get you up to 65. 3.55 gear set from Patrick's Here is a link to Patrick's web site: Patrick's Good luck! Kurt | | |
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