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#24253 12/05/2002 3:12 AM | Joined: Feb 2002 Posts: 22 Member | | Member Joined: Feb 2002 Posts: 22 | will this transmission mate up to any chey inline 6, are there better choices?? | | |
#24254 12/05/2002 5:55 AM | Joined: Feb 2001 Posts: 1,897 Member | | Member Joined: Feb 2001 Posts: 1,897 | Yes and Yes  Depends on what you want to do.
There is enough good in the worst of us and enough bad in the best of us that it does not behoove any of us to criticize the rest of us.
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Be yourself. If you are ever lost, It will be much easier to find yourself if you know who you are!
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#24255 12/05/2002 6:50 AM | Joined: Jun 2000 Posts: 2,773 'Bolter | | 'Bolter Joined: Jun 2000 Posts: 2,773 | What are you mating to? The SM420 fits the bell housing for the 216,235,261 and early 230. The later model SM465 is a bigger box. The bell housing for this one requires a larger center hole, but the older housing can be machined to fit. For more info go to Nowak tranny page
Fred
52 3600
69 C-10
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#24256 12/05/2002 4:24 PM | Joined: Feb 2001 Posts: 1,897 Member | | Member Joined: Feb 2001 Posts: 1,897 | Nowak??? I thought it was Novak :p
There is enough good in the worst of us and enough bad in the best of us that it does not behoove any of us to criticize the rest of us.
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Be yourself. If you are ever lost, It will be much easier to find yourself if you know who you are!
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#24257 12/05/2002 5:28 PM | Joined: Nov 2000 Posts: 1,966 'Bolter | | 'Bolter Joined: Nov 2000 Posts: 1,966 | Thanks for the link to Novak. Great info source for the SM420 and other trans. For a 55 year old design, still a good trans. GM used it in trucks with 230/250/292 I6 and V8s through '67. I knew the 420 was sought after by jeepers and other off road/mud runner types. I had the original one in my '50 3/4 ton pickup behind a 307 SBC. That 2-piece driveshaft with front half torque-tube was strange though. I couldn't stop mine from leaking around the seal.
Professional Novice
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#24258 12/06/2002 4:04 PM | Joined: May 2001 Posts: 1,904 'Bolter | | 'Bolter Joined: May 2001 Posts: 1,904 | Frank50,
Check my above homepage for how I solved the leaky torque tube problem. When I get mine back together, I hope to lose most of the kitchen ware.
1948 3/4-Ton 5-Window Flatbed Chevrolet 34 Years. Now with a '61 261, 848 head, Rochester Monojet carb, SM420 4-speed, 4.10 rear, dual reservoir MC, Bendix up front, 235/85R16 tires, 12-volt w/alternator, electric wipers and a modern radio in the glove box.
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#24259 12/07/2002 4:16 PM | Joined: Feb 2002 Posts: 22 Member | | Member Joined: Feb 2002 Posts: 22 | I would like to keep the stock drive train and either use a small block 350 or a modern inline 6 as in 70's nova | | |
#24260 12/07/2002 7:47 PM | Joined: Mar 2001 Posts: 316 Member | | Member Joined: Mar 2001 Posts: 316 | If you decide to use the SM-420 with a newer engine, (which may have the newer bellhousing, the one with no crossmember under it); you could get a piece of 5" XX wall steel pipe, about 3/4" thick and have it machined down to fit the opening and press-fit on to the SM-420 bearing retainer. I have had this done, but it was several years ago, so I'm not sure about the actual dimensions.
GM Truck, four speed standard transmissions. Built by Muncie.
Installed in: 1947 - 1967 Chevrolet and GMC trucks up to 2 1/2 ton.
Model: SM-420 - Bearing Retainer/Bell housing opening size - 4 11/16"
Gear Ratios
1 - 7.06
2 - 3.58
3 - 1.71
4 - Direct
R - 6.78
Oil Capacity
5 1/2 pints
Installed in: 1968 - 1991 Chevrolet and GMC trucks up to 2 1/2 ton.
Model: SM-465 - Bearing Retainer/Bell housing opening size - 5 1/8" Gear Ratios
1 - 6.55
2 - 3.58
3 - 1.57
4 - Direct
Length - 12"
*** GMC ***
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#24261 12/07/2002 7:58 PM | Joined: Feb 2001 Posts: 1,897 Member | | Member Joined: Feb 2001 Posts: 1,897 | There are a variety of 420 transmissions that were used from 55 up that have a rear output yoke for the open type drive-line.Some have a flange and a park brake and drum assembly on the rear of the tranny with an open driveline. 
There is enough good in the worst of us and enough bad in the best of us that it does not behoove any of us to criticize the rest of us.
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-
Be yourself. If you are ever lost, It will be much easier to find yourself if you know who you are!
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