You'll rarely see a T5 break at launch. Third gear is the natural weak spot in the T5 and from my experience it usually breaks from missing the 2-3 shift or even just consistently being late on the shift. After a while, being late takes the edge off the teeth and starts cracks in them. Then one day.....BOOOOOOOOM......all the teeth come off right along with all of the third gear teeth on the countershaft. Number one mode of failure in the T5. The gate in the tailshaft housing can also help promote this when you begin to wear off that sharp point that makes the clean shift from second to third. That's why people are always looking for new tailshaft housings.
Pro-shifting is when they modify the gearset so that the synchros are no longer needed. Very light clutch effort is required to disengage the current gear and then it slides right on into the next gear. Does away with the ability to downshift though so its not recommended for street driven cars. Liberty and Hanlon both sell pro-shifted gearsets.
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Jeff Chambers
Trophy Stock #3
11.97 Seconds / 114.5 MPH
Chambers Racing Team