Rear differential ratio
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- Sweptline.ORG Member
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Rear differential ratio
I have a 1963 Dodge D100 that had a factory 6 cylinder and 3 speed manual . I have changed it to a 360 magnum with 727 automatic transmission. When I drive on highway the rpm is really high . What would be a good gear for the rear differential. I think it has a 391 in it now . Thanks
- martincom
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Re: Rear differential ratio
Tire size is also a factor and we would need to know that for a recommendation. I'm thinking 3:23, but would need to know tire size to be sure.
1*1971 D100 318 A/T
1*1970 Charger R/T 440-6PK A/T
2*1969 Daytona Charger 440 A/T
1*1969 Coronet R/T awaiting restoration
1*1969 Torino Talladega awaiting restoration
1*1970 Charger R/T 440-6PK A/T
2*1969 Daytona Charger 440 A/T
1*1969 Coronet R/T awaiting restoration
1*1969 Torino Talladega awaiting restoration
Re: Rear differential ratio
If you change out the complete third member which is the easiest way to go make sure to check if current one is open or limited slip. You want to save the limited slip. Expensive part.
Re: Rear differential ratio
I put a 2.94 in my '65 D100 with a 318/NP435. It fits the bill for me.19531963 wrote: ↑Wed Jul 07, 2021 7:25 pmI have a 1963 Dodge D100 that had a factory 6 cylinder and 3 speed manual . I have changed it to a 360 magnum with 727 automatic transmission. When I drive on highway the rpm is really high . What would be a good gear for the rear differential. I think it has a 391 in it now . Thanks
A 3.23 is a good choice as well and probably a bit more readily available.
John
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Re: Rear differential ratio
If you have the tapered axles, dump that POS and get a later rear end with parking brakes.19531963 wrote: ↑Wed Jul 07, 2021 7:25 pmI have a 1963 Dodge D100 that had a factory 6 cylinder and 3 speed manual . I have changed it to a 360 magnum with 727 automatic transmission. When I drive on highway the rpm is really high . What would be a good gear for the rear differential. I think it has a 391 in it now . Thanks