According to my Olds parts book the 64-66 F-85 knuckle is part number 385091 while the 67-69 drum knuckle is 407017 and the disc one is 405982. I know the difference between a disc and drum knuckle but why are 64-66 a different number? According to what I've found the bearings and spindle thread is the same as 67-72 so I'm really curious as to the difference. I thought 64-72 knuckles were interchangeable but maybe they're not? Anyone know?

 

All 64-72 A-body, 67-69 F-body, and 68-74 X-body spindles interchange. Yes, there are different part numbers in the parts book, and Hollander also claims that they are different, but I have swapped many, many spindles among various years with no problems. Put 72 Monte discs on a 65 Cutlass, for example. I have yet to see what the differences are.

 

Thanks Joe, appreciate the info!