by WarWagon » Sat Aug 05, 2017 12:41 pm
Easy way is: count the number of bolts attaching the trans to the diff. 4 bolts= '65
6 bolts='66 and later.
Positrac can be identified by removing the diff top cover plate and looking down at the two side bearing adjusters for the diff carrier. If one is wider than the other it's a positrac if they are the same it's an open diff
Adam Knoll
Fairmont, W.V.
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