just curious about the differences in the a-body platform from 68-72 and 73-77.my 72 and my 76 both share the same wheel base at 112 inches.
there is an obvious difference in rear differentials ,but the rear trailing arms seem to be the same .are the front control arms drastically different?are the body mounts in the same same locations ?is anyone aware of a parts crossreference between the two ?are the actuall frames the same with different parts bolted to them?looked all over for this info with no luck . thanks

 

Completely different frames. The 73-77 cars are wider and longer (I think).

 

Thanks for responding randy. You're right about the width . The more I compare the two the less similarities I find .im hoping the 72 abody tailpipes will work on my 76 .the reason I asked this I was thinking it might been easier to order some parts for a 72 since they are more readily available .

 

The 1973-77 A-body cars are very different from the earlier ones. Spindles have integral caliper mounts and steering arms. Ball joints and bushings are completely different (including different taper angles on the ball joint and tie rod end studs). Yes, width is very different, as are suspension arms. Actually, the 73-77 A-body cars have much in common with the 77-96 B/C-body cars, as GM used the large A-body platform as the basis for the downsized 1977 B/C-body cars.