I want to widen the rear axles on my 66 to match the front. I have installed AIM I beams using a 78 donor for disc brakes. I saw a post a few months back about using later model axle housings but can't find the info. Does anyone know what years the 9 inch that will fit my leaf springs without changing the perches? Thanks.

 

Hard core, You can use 73 to 86. You will have to relocate the mount points.

John

 

Ford also used the 9" rear in their larger cars and vans. The axle lengths and spring perch/shock mount placements varied. You might want to check out the possibilities there, but based on my own research into this a few years ago, the truck axles were unique in their application.

'57-'72 truck axles are of the same dimensions.
'73 and later are not only wider (longer), but sit under a wider frame. To use on on a '72 or earlier, you will have to cut off and re-locate the spring perches and the shock mounts. If you choose to run wide tires, you'll need to use wheels with more offset. (How much offset, I don't know.)