Replacing 62 rearend with a 72 rearend

[72cs20]

Hello all,

I've got a line on a 72 C20 trailing arm rear axle with 4.11 gearing. I'm thinking this would be a good swap into my 62 C20.

Question - Can just the 3rd member be swapped or does the complete axle need to swapped ?

Thanks.

[Palf70Step]

There is differences in the splines between the early years and the 72. I just had a shop do a changeover for mine and found out about the spline count differences between the early years (pre 66 I believe) and the later 12 bolt.

It can be done, but it would be probably easier to do the entire axle. It will be a 1.5" wider axle overall, but will work.

[Shaky]

Is there a difference on the track bar? I have a '71 rear in my '66. My buddy says my truck is "crabbing". I haven't done any measuring yet, but I'm using the '66 track bar and wondering if I need an adjustable one.

[72cs20]

Yes, I believe there are track bar mounting differences to take into account.