[eschaider]

The potential for optical illusion is real however if you look at the tooth damage on Fordfan's gear and on the other transmission they replicate each other. The telltale evidence is the reduced levels of damage on both driving and driven gears where they don't engage each other. The lack of engagement (and damage) is caused by the misalignment of the two gears.

The only question that remains, in my mind, is whether or not this is a problem endemic to all TKOs (maybe 500s also?), a particular production run at Tremec or the result of the 'tune up' that Keisler provides for those who opt to buy it.

This is a product quality assurance problem that originated either at the manufacturer or the reseller after they tweaked the unit. The fact that the reseller would attempt to blame the damage on a partially engaged gear is astounding and troubling. Third gear does not slide and missed shifts simply cannot produce this type or level of damage.

The only thing that would produce this type of non-uniform damage across the face of the gear is a torque load in excess of the transmission capacity of two misaligned gears. The problem would only manifest itself when the final drive was hooked up and an engine of sufficient torque output was on the input shaft side of the transmission.

The average Cobra especially a high powered one (600 ft-lbs torque or more) would probably not be able to create the load conditions necessary for failure without very sticky tires because we smoke the tires and unload the drive train (still not good). It is a very different story with a 3500-3800lb door slammer with decent tires and only 500 or so ft-lbs of torque. If you loose 20-25 % of the tooth face engagement you now have a torque capacity of 450-480 ft-lbs best case. Suddenly we now have all the conditions necessary for an ultimate strength failure on the reduced face contact gears. I think it is a virtual certainty that this is what happened.

Ed

p.s. I'm still too much of a green horn on the site, I don't yet know how to paste a picture into this email, so I'll direct you to the picture instead. Look at Anthony's post #141 he has a more straight on view of the other box. Look at the back of the third gear synchronizer dog teeth and look at the proximity of the countershaft gear. It is almost touching! Look at the machined space between the dogs and the gear teeth on the mainshaft gear. Big space! This offset is what the countershaft gear should show between itself and the third gear synchronizer dogs. This misalignment reduces the torque transmission capacity of these two gears. This is the source of the failure.