There's been a lot of confusing information about carrier swaps in 8.25 diff housings so I figured I would share my journey for anyone in the future who is looking for information.
A couple weeks ago I snagged an 8.25 A-body differential from a 74 Swinger with an unknown gear ratio. After I got it out and home it turned out to be the dreaded 2.45s! This diff is to upgrade the 7.25 diff with 2.76 gears I currently have in my duster. But 2.76 to 2.45 is even worse! So I started researching ring/pinion swaps. Some said it can't be done because the 2.45 has a "special offset housing" and some said you just need the right carrier so I decided to stay my course and swap parts into this housing.
There is only ONE 8.25 HOUSING, but if you want lower gears you will need to change your carrier, and carrier bearings to suit. The carrier must be pre-1997 due to the axle spline switch from 27 to 29. In the pics you can see how huge the 2.45 pinion is compared to the 3.55 pinion, this is part of the reason why the entire carrier needs to be changed. I pulled a ring/pinion/carrier from a 1995 Dodge Dakota Sport with an 8.25" and 3.55 gears and am in the process of getting this swap done. If you are using a later model carrier in your early housing, you will need to change the carrier bearings. The early housings use a smaller O.D. carrier bearing. The I.D. is the same so just get the correct bearings for a 1974 to put on your 80's or 90's carrier. I am using a Yukon Gear rebuild kit, part #YK C8.25-A. So far I have the housing cleaned, painted, new races installed, and pinion installed with new bearings and preload set to 20 inch pounds of rotational force. The carrier still has the wrong bearings on it but it still runs smoothly test fitting everything together. My end goal is to have a cost effective upgraded rearend for my duster built with parts I can find locally and share some pictures here and there of the process along the way.
A couple weeks ago I snagged an 8.25 A-body differential from a 74 Swinger with an unknown gear ratio. After I got it out and home it turned out to be the dreaded 2.45s! This diff is to upgrade the 7.25 diff with 2.76 gears I currently have in my duster. But 2.76 to 2.45 is even worse! So I started researching ring/pinion swaps. Some said it can't be done because the 2.45 has a "special offset housing" and some said you just need the right carrier so I decided to stay my course and swap parts into this housing.
There is only ONE 8.25 HOUSING, but if you want lower gears you will need to change your carrier, and carrier bearings to suit. The carrier must be pre-1997 due to the axle spline switch from 27 to 29. In the pics you can see how huge the 2.45 pinion is compared to the 3.55 pinion, this is part of the reason why the entire carrier needs to be changed. I pulled a ring/pinion/carrier from a 1995 Dodge Dakota Sport with an 8.25" and 3.55 gears and am in the process of getting this swap done. If you are using a later model carrier in your early housing, you will need to change the carrier bearings. The early housings use a smaller O.D. carrier bearing. The I.D. is the same so just get the correct bearings for a 1974 to put on your 80's or 90's carrier. I am using a Yukon Gear rebuild kit, part #YK C8.25-A. So far I have the housing cleaned, painted, new races installed, and pinion installed with new bearings and preload set to 20 inch pounds of rotational force. The carrier still has the wrong bearings on it but it still runs smoothly test fitting everything together. My end goal is to have a cost effective upgraded rearend for my duster built with parts I can find locally and share some pictures here and there of the process along the way.
