77 to 73.5 aluminum trailing arms swap

[ssinparadise]

Hi there. Just bought a pair of aluminum trailing arms from a 77. This included hubs and emergency brake assemblies. I searched for the topic on early steel to later aluminum trailing arm conversion but still have questions on what parts are needed. My main questions have to do with the hubs, cv joints and flanges. I realize the bearings are larger in the aluminum arms, so how does this effect the use of my 73.5 axles? Do I need to use axles and flanges from a later (post 73) car? Would love to hear from those with 73s that have done this upgrade,since it seems that there are additional issues with the earlier cars that may not apply here. Thanks

Scott S
73.5 911
74 914 2.0

[Bobboloo]

I'm going off of memory here but I believe this is a straight swap considering your installing 77' arms. Your 73.5' 4 bolt axles should bolt right up. I believe they went to the 6-bolt axle in 78' but I'm not sure. Also if you have a 73' stock rear sway bar then you already have the proper fitting (ball joint) on the aluminum arms for your swaybar. Doesn't get much easier.

[Chuck Moreland]

77 has 6 bolt CV. Swap the stub axles with the ones from your 73.5 and you are golden.

[Chuck Moreland]

The al arms use the larger late style wheel bearings. These will accept your early 4 bolt stub axles just fine, but you will need to buy new bearings since the old ones will be destroyed upon removal of the stub axles.

Your shocks will bolt up just fine. The shock bolt size changed in 72 so you already have the later ones.

[randywebb]

This is exactly what I did with no problems. It's been years but I don't even recall issues with the stub axles...

[tom1394racing]

I did just this on my RSR clone. I only needed to swap the inner stub axles from my '73.5 arms onto the '77 arms to make this work.

check this post;
Do 87 trailing arms work on a 72???? and other ?????