I was hearing a clinking sound like a heat shield rattling for about 4 months. Well a few days ago it finally let go when driving down the street. I went to get on it and the RPM's went straight up to red line. I figured the trans pump went out or torque converter but when i pulled out the trans i saw that the flexplate was broken. The center section still bolted to the crank but the rest of it just sitting there. I was just wondering if anyone else has experienced a problem like this before?

Zach

 

While I haven't heard of it on the Lightnings, it is not an uncommon problem with flex plates. They are made of mild steel and as such are subject to stress cracking. The ring gears, which are welded to the outside of them, are usually better material. But the flex plates themselves are stamped from "commercial quality" steel which can vary widely in composition. The lighter the flex plate is, the less rotating inertia there is, so they are designed to be a balance between light weight and structural integrity. The Lightning flex plates are not doweled, so the sheer tension of the bolts have to transmit all the load. If the bolts were not properly torqued at assembly and the flex plate was made from a piece of material that was on the low end of tolerance in thickness, the failure may have been inevitable.