Cracked rim on 2007 2500hd classic
Just sharing. During pre-trip inspection my son and I found this cracked rim on my truck. It was a surprise and was even more surprised to see the weight rating on the back of the rim. This is...
Forum Discussion
3 tons wrote:
AFAIK, alloy rims in heavy duty applications (e.g. 3/4 & 1 ton) are forged and not cast…A forged wheel will NOT manifest a crack, but it will twist (*not unlike a popcorn kernel)…Most after market wheels are cheap ($$) because they are not forged, and I see these wheels on wannabee HD trucks all the time (tough guy looks trump safety and common sense…), even with heavy campers on them…Soon to be winners of the Darwin Award…
* for the unqualified naysayers, this IS what happened to my alloy Dually wheel when broadsided by a woman on a cell-phone - yes, forged aluminum will TWIST and wadd up exhibiting NO SIGNS of a crack…
3 tons
Aluminum is malleable but not ductile.
Steel is both malleable and ductile.
A common example of how that works, Outboard legs are typically aluminum. If the bottom skeg gets bent from hitting a log:
- If you grab it with a big set of vice grips and try to bend it back, it will typically break off...because it's not ductile.
- If you place a wood block to stop it moving and use a hammer to pound it back into shape, it typically works without cracking because it is malleable.
Ductile is the ability to bend and stretch without failure.
Malleable is the ability to be hammered or beat into a new shape.
So depending on how the failure occurred, the rim could simply bend/twist the metal or it could crack the metal.
