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| | | | Joined: Mar 2005 Posts: 684 Shop Shark | | Shop Shark Joined: Mar 2005 Posts: 684 | What would be a good donor truck to look for to acqure a Overdrive transmisson to go behind a 261 in my '49 6400? | | | | | Joined: May 2005 Posts: 8,878 . | | . Joined: May 2005 Posts: 8,878 | Dodge (preferred) or GM with, the NV4500 transmission, 5 speed OD. Do a search to find out how to install it once you find it. Advance Adapters makes an adapter I think. https://www.stovebolt.com/ubbthread...0&topic=0&Search=true#Post374226"bigbadswingdaddy" seems to be the expert on 6 cylinders with NV4500's. Do you need a transmission with a parking brake? Grigg | | | | | Joined: Mar 2005 Posts: 684 Shop Shark | | Shop Shark Joined: Mar 2005 Posts: 684 | Thanks for the quick reply Grigg. I presently have a transmisson park brake and suppose I would like to retain that. Would that be possible? I will start looking for the NV4500
Cleon | | | | | Joined: May 2005 Posts: 8,878 . | | . Joined: May 2005 Posts: 8,878 | Not sure if the NV4500 was offered with one, but I think so, possibly in an RV chassis? Or something with rear disc brakes? The folks at Advance adapters should know, they seem to be NV4500 experts. I have a book they published about the NV4500, with lots of info and measurements and part numbers, but I can't seem to find it now..
Grigg | | | | | Joined: May 2005 Posts: 8,878 . | | . Joined: May 2005 Posts: 8,878 | Or perhaps a Fuller 6 speed, model number starting with FSO... FSO-6406A, or FSO-8406A. I don't know much about those though, or how easy they are to find, only in reasonably new trucks, medium duty size. OD ratio is 0.78, first gear is 7.05, weight is about 375# installed including oil. Could be more weight than you are looking for, and a custom adapter may be needed unless you can find an SAE flywheel housing for your engine?
Allison 6 speed, same size as from a Duramax, has about 0.64 for the second OD ratio. That is about as good as you will find for an OD ratio. I know of a new never used one for sale, with all the electronics to work on a non computerized engine, price is realistic, but expensive none the less.. Not sure how you would attach it to the 6 cylinder? I believe it has an SAE housing on the transmission.
Grigg | | | | | Joined: Mar 2005 Posts: 684 Shop Shark | | Shop Shark Joined: Mar 2005 Posts: 684 | Well, lots to think about Grigg but the NV4500 sounds like the way to go. Might even be able to work out a parking brake drum on the short drive shaft before the carrier bearing
Cleon | | |
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