[GuyH]

Hi All, long time lurker here. I have a '67 Firebird 400 w/TH400. The diff needs a rebuild & I have some questions I'm hoping the community can help with. I use the car for back road and freeway cruising spring through fall seasons & have no intention of using it on the track or auto-crossing etc, just spirited fun driving. Have no plans or need to rebuild the engine at this stage, though for this car I wouldn't expect that any future engine refresh I'd have done would result in more that 425 or so hp.

The diff is an open 8.2 10 bolt BOP non C clip unit (original to the car) with a 3.08 ratio & is making noises I can't in good faith keep ignoring (I replaced the rear wheel bearings over the summer & was hoping that was the source of the noise, alas I was sadly mistaken ). I'd like to keep the 3.08 ratio.

1) Since I'm going there, should I install a posi unit? Appreciate this is totally subjective, but for those who have made the change does it make a big difference to the driving experience?

2) If yes to posi, I found an Auburn unit that will fit a 3.08 ring & pinion (p/n 546099) that seems decently priced. Is Auburn a good brand or should I consider others?

3) Should I replace the ring & pinion? No clue if the current pair are still good or not, I sense the noise is just bearing related, but is it good practice to replace as part of a rebuild?

4) If I do replace the ring/pinion, what's a good brand? Both Richmond Gear & Motive Gear make replacement 3.08 sets, is one preferable to the other or should I consider another brand? (eg Jegs sell a set in their own name for 10 buck less than the Motive Gear set they have listed)

5) Am I just overthinking this &, for the driving I do, should I get one of those no name rebuild kits that includes a posi unit & ring/pinion set off ebay?

Thanks in advance for your help guys, appreciate any comments, info, thoughts etc.

Guy