how are they for offroad apps? (i.e. the '03 in my sig)

drj

 

You should look into the shear strength of the two different materials.

 

thats what i was wondering...whether or not the aluminum would be strong enough in a worst case scenario (which is the ONLY time it matters!!)

drj

 

The guys in the chebby trucks have driveshafts made from aluminum, and so do some of the F-150's. Here is the downside. They require a differnt wall thickness than other materials, but do dampen harmonics a bit better, and transfer less vibration than other materials. Due to the different materials they are often one piece units and have to be a very large diameter. Given the larger diameter, they are subject to impacts and are easily ruined. a steel shaft is more forgiving, and might last the ride home, where as the softer aluminum material would fold.
In a 4wd application, I am really not seeing too many advantages, at least not enough to run one.

 

thanks - thats what i needed to know.

drj

 

Not only does steel have a much higher elastic (Young's) modulus which means that it tends to not bend, but it can also be reformed when damaged, unlike aluminum (which has a tendency to break under stress).

BTW, if you are worried about the balancing aspect of steel driveshafts, you should look into this product:
http://www.balancemasters.com/driveshafts/index.html