Originally Posted by marcus7' date='Apr 28 2004, 10:34 AM

If I understand how the transmission works, my FC NA manual has what Mazda refers to as a hub assembly (AKA engagement collar). The synchros are attached to both sides of the hub assembly (each side is used for a different gear). When I shift, the cone on the gear, which is male, slips into the cone shaped area of the synchro, which is female. The friction between the two is used to speed up the hub and associated gear to match the rotational speed of the shaft so that they are both moving at the same speed before the dog teeth are engaged.



The only time the hub and or gear will stop moving is if the transmission's mainshaft is still (the car is not moving). Are you breaking parts while waiting at a light, or is the car moving at the time?



If a car is moving, and someone pushes too hard on the shifter before the hub and the shaft speeds have been synchronized, the sychro ring can overheat (hot spots and excessive wear), and/or the dog teeth can be slammed into position damaging the teeth on the gear, hub, or both. I've never heard of the syncro ring itself breaking, but like I said, I'm not a transmission tech and I suppose anything is possible. What you're describing really sounds like broken dog teeth, as that is what causes the grinding noise, not the synchro itself.



If the car is sitting still when the damage occurs, there is a clutch problem.

Originally Posted by f.t.p. rotaryrocket' date='Apr 30 2004, 06:41 AM

but an s4 turbo engine is putting out that much power and you guys are telling me that the n/a tranny can't handle like 170 lbs of torque. the 95' z24 cavalier came with 185 lbs of torque and hte rx7 tranny is that much of a bitch???

Originally Posted by j9fd3s' date='Apr 30 2004, 07:53 AM

wtf does the na rx7 tranny have to do with your french car?