What should I do with the clutch at a stop?

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Have you ever wondered what to do with the clutch and transmission of your manual transmission car at a stop light? You have essentially two choices: clutch out, transmission in neutral, or clutch in. Here's why the best choice is clutch out:

In the MTX-IV manual, as with all manual transmissions these days, ALL the gear pairs are in constant engagement. Each gear pair has one gear fixed to the mainshaft which is connected to the clutch, while the other gear spins freely on the countershaft. There are 2 countershafts in the MTX-IV, one for 1st thru 4th gear, and a second for 5th and reverse. The countershafts are geared-to and drive the differential by another pair of gears called the ring and pinion. To select a particular gear, one of the shift forks slides a synchro cone, that is splined to the countershaft, until it engages with its respective free spinning countershaft gear. The free spinning gear is now locked to the countershaft by the cone and power is transmitted from the mainshaft to the countershaft and on to the differential and drive wheels.

The wear in neutral with the clutch engaged, is spread between all 5 countershaft gears, because they're all free-spinning. Even when one particular gear is selected, the other 4 unselected gears are still spinning freely on the countershafts. The amount of time spent idling in neutral is a fraction of that spent cruising down the highway, spinning ALL the gears madly. At any given time, the 4 unselected countershaft gears will be spinning at different rates with respect to their countershafts.

I maintain (and the builders of racing clutches will back this up) that the worst thing you can do to a clutch is to sit there with the pedal to the floor, overstroking the diaphram spring. This overstresses the diaphram and gradually lowers the clutch clamp load.