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| | | | Joined: Jul 2003 Posts: 22 New Guy | | New Guy Joined: Jul 2003 Posts: 22 | I'm interested in changing the ratio of a 3/4 ton R/e . IIt looks like they used this R/e for decades so it seems that there should be several different ratios used in the same basic housing. Am I on the right track or dreaming?
Cheers
Greasy Thumbs
| | | | | Joined: Jun 2000 Posts: 2,773 'Bolter | | 'Bolter Joined: Jun 2000 Posts: 2,773 | IF you do a search of this forum, you will learn that your choices are extremely limited. Assuming you have the 4.56 gears, you can get the pumpkin out of a 64-72 with 4.10 gears. A few 3.73s are out there, but about as scarce as hen's teeth.
Another option is to go with a later model differential, which is about 3.5" wider. Width is partially offset with newer rims which have more setback. With a 12 bolt, you can get 3.73 gears and still have a round housing. The bulletproof 14 bolt has a flat sided housing, but can be found with 3.42 gears. Cost around here for the 14 bolt is in the $300-350 range, 12 bolts are a lot cheaper.
Fred
52 3600
69 C-10
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#6599 08/20/2003 11:50 PM | Joined: Mar 2002 Posts: 9,115 'Bolter | | 'Bolter Joined: Mar 2002 Posts: 9,115 | There is also a new 3.90 gear set available which can be installed in some of the more modern versions of the pumpkin. American Classic has them listed as if they install right into the AD trucks, and that is incorrect. They install into 1959 to ?? pumpkins as stated by their supplier, Randy's pinion and gear. | | | | | Joined: Jul 2002 Posts: 385 'Bolter | | 'Bolter Joined: Jul 2002 Posts: 385 | T'nix, are you sure about the 3.90 not fitting the AD tonner? When I took the Juggernaut to Randy's they said they could do 3.90's but they would have to make a custom carrier bearing (more expensive and would take a week rather than a day). I'm cheap, and there's not much of a numerical difference between those and the 4.10's I opted for. | | | | | Joined: Feb 2001 Posts: 1,897 Member | | Member Joined: Feb 2001 Posts: 1,897 | 4:10 pumpkins are easy to find,,,,, if you look in my garage  I found out that a 10-bolt rear end out of a 79 cadillac Fleetwood Broughm de Elegance has a rear disc brake equipped rear end and measures 61 & 1/4 from wheel mounting flange to wheel mounting flange  The measurements for the 1/2 ton,,47-54 & 55 1st Series Chevy Truck 60-62" And the 55 2nd series to 59...55-59 Chevy Pickup 62" I think the 3:73 ratio pumpkins are in big block equipped Suburbans from the 69 to 72 era.
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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#6602 08/21/2003 11:51 AM | Joined: Mar 2002 Posts: 9,115 'Bolter | | 'Bolter Joined: Mar 2002 Posts: 9,115 | Hedgehog,
that is what I am talking about. The 3.90 gear set is not a drop in for the AD pumpkins. However American Classic lists it as so and I talked to them on the phone. They gave me Randy's number to get more information.
I agree that 3.90 is not much different from 4.11 . | | |
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