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| | | Forums66 Topics128,022 Posts1,055,386 Members48,422 | | 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!
Lots of work on Brad's part ... pure enjoyment (and references) for you!
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For helping keep this great
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on the Internet for over 30 years! and not clogged down with Ads! Again, thanks! | | | | Joined: May 2014 Posts: 75 'Bolter | | 'Bolter Joined: May 2014 Posts: 75 | Would a three speed transmission from a 1947 truck fit my 1951? mine is a 3600 model and I don't know what model the 47 came from. Both have the 216. Brad. | | | | | Joined: May 2006 Posts: 8,351 'Bolter | | 'Bolter Joined: May 2006 Posts: 8,351 | I'm pretty sure the bolt pattern on the bellhousing is different.
Bill Burmeister | | | | | Joined: Mar 2010 Posts: 10,270 Renaissance Man | | Renaissance Man Joined: Mar 2010 Posts: 10,270 | The torque tube parts are different from a 3100 vs a 3600.
1952 5-window - return to "as built" condition | 1950 3100 with a 235 and a T-5 transmission
| | | | | Joined: Sep 2001 Posts: 29,269 Bubba - Curmudgeon | | Bubba - Curmudgeon Joined: Sep 2001 Posts: 29,269 | I think the length of the transmissions are also different 47 vs 51? | | | | | Joined: May 2014 Posts: 75 'Bolter | | 'Bolter Joined: May 2014 Posts: 75 | Ok if the 47 trans wont bolt up directly, what about the internal "guts" of the trans, were they basically the same? I have problems internally with the 3 speed on my 51 3600 and I can get two used 47 3 speeds, I don't what condition they are in, and was hoping I could just swap out the parts I need and get the 51 speed working properly. I don't know exactly what is wrong with the 51 3 speed, I just found these 2 47 3 speeds for a great price. Brad. | | | | | Joined: May 2014 Posts: 75 'Bolter | | 'Bolter Joined: May 2014 Posts: 75 | I just realized I posted this in the ENGINE section of the forum...should I post this in the DRIVELINE section instead? Brad | | | | | Joined: Jan 2001 Posts: 5,337 'Bolter | | 'Bolter Joined: Jan 2001 Posts: 5,337 | A lot but not all of the parts will interchange. Here are two links to my blog on transmission interchange. Transmission bolt patterns. Transmission lengths.
See the USA in your vintage Chevrolet! My Blog | | | | | Joined: Jun 2011 Posts: 5,096 Crusing in the Passing Lane | | Crusing in the Passing Lane Joined: Jun 2011 Posts: 5,096 | If the '47 trans is a 420,then it will fit if the drive lines are the same, if it is an earlier trans(for got the MN) then no,bolt pattern is different. A 465 would also fit.
'37 GMC T-18 w/ DD 4-53T, RTO-610, 6231 aux., '95 GMC running gear, full disc brakes, power steering, 22.5 wheels and tires. '47 GMC 1 ton w/ 302, NP-540, 4wd, full width Blazer front axle. '54 GMC 630 w/ 503 gasser, 5 speed, ex fire truck, shortened WB 4', install 8' bed. '55 GMC 370 w/270, 420 4 speed, grain, dump bed truck from ND. Works OK.
| | | | | Joined: Jan 2001 Posts: 5,337 'Bolter | | 'Bolter Joined: Jan 2001 Posts: 5,337 | SM420 did not start until 1948.
See the USA in your vintage Chevrolet! My Blog | | | | | Joined: May 2014 Posts: 75 'Bolter | | 'Bolter Joined: May 2014 Posts: 75 | I'm going to move my post to the driveline forum. Thanks everyone. Brad. | | |
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