Transaxle autopsy < Previous | Back to index | Next>

The pinion shaft nut is the most critical one. It's a left-handed nut, meaning it unscrews clockwise instead of the normal counterclockwise. It also has to be torqued to the highest value. This high torque was a problem for the original type of lockwasher that Saab used (seen at left.) This type of lockwasher has a thin tab that fits into a slot on the shaft to keep it from rotating. You'd fold over the dished shoulder of the washer by tapping it with a hammer, to lock it over a flat of the nut. The problem: Often, when you tried to torque the nut (bottom) it would put so much drag on the washer that the tab would break off -- as it has on this washer. So, Saab substituted an improved type of washer and nut (seen at right.) With this hardware, the washer is much thicker, so its tab is less likely to break off. This washer is too thick to fold over, so instead the nut has a wide, flat shoulder. You tap a spot on this shoulder with a chisel, to bend it down into one of the three slots around the edge of the washer.