Wow. Thanks. Looks pretty involved.See this thread. I have read everything but its very helpful! Are you doing the swap or are you taking it to a shop?
https://www.forabodiesonly.com/mopar/threads/the-8-1-4-thread.350667/
View attachment 770092 I have a 8.25 one legger with 10 bolt cover rear end in my ‘70 Belvedere with 276 gears. I know a guy that’s selling a 8.25 carrier, 27 spline, sure grip with a 3:21 ratio gear for $300. Are my axles 27 spline? Would this be a direct swap into my housing? Any other info would be appreciated.
Yes, they will be 27 spline unless someone charged them. While it's not really meant for heavy duty use, it's a light rear end that is pretty easy to find and will apparently hold up well, within certain limits. I'm going 3.91 with a Sure Grip because I'm never on the highway. Even if I do, the formulated difference in rpm with my tire and the 904 is only 300 from a 3.55 to a 3.91 at 60mph. 2800 vs 3100. Not a game changer for me for the kind of driving I do.
@dyolf82 what is disagree for?? Maybe I can clarify.I just upgraded my 8.25 to suregrip and 3.55 from open 2.71. My buddy did the swap with me assisting (I have never done and special tools needed). Only issue we had was that the Motive installation kit I purchased had the wrong carrier bearings for some reason. We had to get the part number off of my old bearings and found National (US made) locally to use.
After that he nailed the contact pattern 1st try. Critical numbers are the pinion bearing before taking apart and the carrier set-up. Followed the instructions in the service manual for my car. Here is the kit I used......
View attachment 831258 View attachment 831259
Then go back and retract it. It is the right thing to do.My bad... must’ve hit disagree by accident lol...