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Mod | | | Forums66 Topics128,164 Posts1,056,983 Members48,458 | | 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: Sep 2006 Posts: 1,997 Big Bolt Forum Co-moderator | | Big Bolt Forum Co-moderator Joined: Sep 2006 Posts: 1,997 | Just saw this on ebay and since I know nothing about this subject I am curious if this is an overdrive for a big bolt? http://cgi.ebay.com/ebaymotors/spic...733QQssPageNameZWDVWQQrdZ1QQcmdZViewItem A day without laughter is a day wasted- Charlie Chaplin When wrestling a grizzly bear, you have to keep at it until the bear gets tired, not when you get tired. 1948 Chevy 2-Ton | | | | | Joined: Sep 2006 Posts: 1,997 Big Bolt Forum Co-moderator | | Big Bolt Forum Co-moderator Joined: Sep 2006 Posts: 1,997 | Found this neat link on the brownie transmissions. http://www.6066gmcguy.org/spicer-5831-b.htm A day without laughter is a day wasted- Charlie Chaplin When wrestling a grizzly bear, you have to keep at it until the bear gets tired, not when you get tired. 1948 Chevy 2-Ton | | | | | Joined: May 2005 Posts: 8,878 . | | . Joined: May 2005 Posts: 8,878 | here is one I have for sale http://www.stovebolt.com/bboard/cgi-bin//ultimatebb.cgi?ubb=get_topic;f=29;t=003005 | | | | | Joined: Sep 2006 Posts: 1,997 Big Bolt Forum Co-moderator | | Big Bolt Forum Co-moderator Joined: Sep 2006 Posts: 1,997 | Which letter suffix do you have on that tranny? A day without laughter is a day wasted- Charlie Chaplin When wrestling a grizzly bear, you have to keep at it until the bear gets tired, not when you get tired. 1948 Chevy 2-Ton | | | | | Joined: May 2005 Posts: 8,878 . | | . Joined: May 2005 Posts: 8,878 | None. It is a 0.73 overdrive. Grigg | | | | | Joined: Sep 2006 Posts: 1,997 Big Bolt Forum Co-moderator | | Big Bolt Forum Co-moderator Joined: Sep 2006 Posts: 1,997 | Ah... I see by the chart on that link I posted above that there are three tranys that have the .73 OD, the others are ones like yours without a letter suffix and the 5831 A and the 5831 E. I wonder how hard it would be to find the linkage, shaft, shifters, and mounting bracket for yours. A day without laughter is a day wasted- Charlie Chaplin When wrestling a grizzly bear, you have to keep at it until the bear gets tired, not when you get tired. 1948 Chevy 2-Ton | | | | | Joined: May 2005 Posts: 8,878 . | | . Joined: May 2005 Posts: 8,878 | The driveshafts are no problem. The mounting stuff can be made from scratch. I have been looking at shifters on cab over trucks, and I think one could be used for the 5831. Or an original could be found in a junk yard, but they are a little hard to find. I have also considered making one. Or perhaps the shift tower from a regular 3 speed floor shift transmission could be used if the shift rails were extended, then attach the linkage to them to go back to the spicer.
Grigg | | | | | Joined: May 2005 Posts: 41 Wrench Fetcher | | Wrench Fetcher Joined: May 2005 Posts: 41 | Grigg, I think I have a similar unit on my GMC with the tandem tag axle. Do these units make a big difference in mileage or top speed. The truck is a '52 or '53 with a 302.
Terry Wofford '52 GMC 3 1/2 Ton '51 GMC 2 1/2 Ton '53 GMC 1 1/2 Ton '53 Chevy 2Ton "If it ain't broke, well give me the keys and I'll be right back!"
| | | | | Joined: May 2005 Posts: 8,878 . | | . Joined: May 2005 Posts: 8,878 | It depends on what ratios you have as to the difference in top speed.
Most have either a .85 or .73 overdrive, they help with top speed.
Some only have direct and two slower gears.
The 6066 link posted above has this info. And if you don't find what you need there I have a good bit of information on them, including the larger sizes.
Grigg | | |
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