Ignoramus23641 wrote:
I have two of these 36" Ridgid pipe wrenches:

http://goo.gl/ZOm4N

One is steel and another is aluminum.

I want to keep one and sell another. My question is which one is
better. Aluminum one is a lot lighter, but is it as strong? Or does it
matter?

I am not a plumber, but once in a while I need to turn something that
does not want to turn, like a stuck engine etc. This is my use.


Hmm.

If subject to too much torque, the aluminum wrench will bend, the iron
wrench will break. "Too much" is probably greater for the cast iron wrench.
How much greater, I know not, nor whether it matters in the real world.