Just picked up a 70k mile 2014 1ss m6 that was owned by an older lady other than a few door dings and chips the outside is pretty clean and the interior is very good. Upon initial service we found everything extremely well taken care of besides slight seal leaks in rear diff. And the posi seems weak to me which I've read is an issue with these diff. The fluids were all clean when drained and overall nothing else out of ordinary. The car will basically be a date night/vacation ride as I've got my 70 restomod Camaro for play and performance. Anyway down to question is the posi unit rebuild able as I've found kits but some of the threads and posts in f b groups say it's a waste of time. Is it better to just replace and if so what are good reliable long lasting options? Thanks.

 

It's true, rebuilding or modifying the stock unit is a waste. I tried it with mine and it did not go well. I ended up having a Detroit TrueTrac installed. It's an awesome unit, completely undetectable in normal driving. A little spendy, but well worth the investment.

 

Go with a True Trac and 3.91 Gears, They make a nice combo in my opinion.