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| | | Forums66 Topics128,090 Posts1,056,024 Members48,432 | | 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: Jan 2024 Posts: 89 'Bolter | | 'Bolter Joined: Jan 2024 Posts: 89 | I am trying to piece together my 1957 235 3100 4 speed floor shifter. And I am confused. I have the shift lever out. Pretty simple. But the boot and floor seal are long gone. The hole in the floor is basically square. The shifter boot and retainer are round. The floor seal is square. Anyone have guidance, or a photo as to how these parts are supposed to go together. Square hole...round peg??? Confusion runs rampant! Thanks in advance.
1957 3100, 235 with 4 speed floor shift
| | | | | Joined: Feb 2016 Posts: 1,987 'Bolter | | 'Bolter Joined: Feb 2016 Posts: 1,987 | I was in the same boat, mine had no boot or seal when I acquired it. I researched available boots and bought a square one from Summit Racing, along with a boot for the park brake lever that was designed for a transfer case shifter.
1957 Chevrolet 5700 LCF 283 SM420 2 speed rear, 1955 IH 300U T/A, 1978 Corvette 350 auto, 1978 Yamaha DT175, 1999 Harley Davidson Softail Fat Boy
| | | | | Joined: Jan 2024 Posts: 89 'Bolter | | 'Bolter Joined: Jan 2024 Posts: 89 | 78, Thanks for the reply. I will persevere a bit longer. but this is definitely an option. Thanks! Any chance you have a Summit part #?
1957 3100, 235 with 4 speed floor shift
| | | | | Joined: Feb 2016 Posts: 1,987 'Bolter | | 'Bolter Joined: Feb 2016 Posts: 1,987 | I probably won't find the invoice, I know I didn't spend much on both of them, less than $30 for both. I had to fabricate a new plate under the transmission boot 'cuz the original was pretty flimsy from rust so it wasn't real important to me that it fit the original opening. I just searched through their pages until I found one with the rough dimensions I wanted at a low price.
1957 Chevrolet 5700 LCF 283 SM420 2 speed rear, 1955 IH 300U T/A, 1978 Corvette 350 auto, 1978 Yamaha DT175, 1999 Harley Davidson Softail Fat Boy
| | | | | Joined: Jan 2019 Posts: 2,242 Herder of Cats, Goats, and Sheep (moderator) | | Herder of Cats, Goats, and Sheep (moderator) Joined: Jan 2019 Posts: 2,242 | This is what I put in my 58: Shift BootIt isn't original, but I am quite happy with how it looks. You can see pics in my DIY thread (link below) | | | | | Joined: Sep 2010 Posts: 2,307 'Bolter | | 'Bolter Joined: Sep 2010 Posts: 2,307 | Sm 420 ? My 54 with sm 420 has the same square hole and under floor sponge but the top boot I ordered was the round if I remember correct it is a large enough diameter to cover the square hole at least on my older truck. | | | | | Joined: Jan 2024 Posts: 89 'Bolter | | 'Bolter Joined: Jan 2024 Posts: 89 | Ahhh... I did not see the obvious! The floor seal is between the floor and the transmission. Duh! Now the pieces fall into place. Thanks!
1957 3100, 235 with 4 speed floor shift
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