Aluminum rear axles?

You must be reading that book I gave you.

I like where this is heading.

It's not cheap, but i believe Currie Enterprises makes a complete 8" aluminum axle housing and 3rd member for say an early Mustang

DANA 40s and DANA 60s were available as aluminum housings in the front of IFS Chevy&GMC trucks, but they had half shafts going out to the front hubs. S10s and Blazers have a similar setup.

Strange offers an aluminum center section for the Ford 9", and I would imagine if you were really clever you could build a fabbed aluminum housing for them.

I would imagine aluminum solid axles do not see much use due in production vehicles due to high cost and their tendency to fail catastrophically rather than incrementally.

Aerostar vans sometimes had an aluminum center with steel axle tubes. No idea what size, I just remember being surprised by one. Plastic back cover, too.

In reply to Curmudgeon:

Like the old hardbody 4cyl r180 front diff and 720 rear diff? I'm not sure, nobody that I know of has compared those guts with the 2gen xterra r180 guts. If youre set on one youd need to do some significant modification to he housing as it's offset with the unequal length shafts. If you go that direction I'd go with the slightly beefier m205 from the titan or the r200 from the hardbody/frontier/1gen xterra v6

Housing mods would be in its future no matter what. I like the idea of an aluminum diff carrier for weight reduction. The HP pushed through would not dictate a 9 inch Ford or similar. In fact, the Spridget carrier might even work. IIRC the stock guts are good to around 125 HP or so but as noted the axle shafts are like spaghetti. But I wouldn't be using the stock axles anyway.

To Toyman: yeah I been readin', studyin' and thinkin'. There's a readily available 90 degree driveshaft adapter setup I need to show you sometime or other.

Hardly grassroots but quick changes are available with aluminum center sections and can probably take anything you want to dish out.

every Corvette made since '84.. there is a 94 Ford Explorer out in my yard awaiting a transmission transplant that has an aluminum center section in the front differential. every newer GM rwd car has an aluminum center section- so cars like the GTO, G8, and Camaro along with the Solstice, Sky, and all those badass rwd Caddies.