tranny problems

Bad motor mounts can wreak havoc on just about anything in your engine bay. Definitely get that fixed if you haven't already. My old Volvo began overheating because the engine rotated enough that the cooling fan couldn't run, and in the 100F heat in the summer the engine would overheat when idling since the radiator didn't get enough airflow. I believe someone else mentioned that bad motor mounts caused his CV joints to fail constantly.

Do check your cable linkage to the shifter, that could be the cause of not being able to shift into certain gears. The stalling problem could be related to that as well. If the cables aren't aligned properly then you may not actually be putting the transmission into the gear you think you are. Neutral position of the shift lever could actually be in a gear, etc.

Once you've inspected all that stuff and either verified it's not the problem or fixed it, and your problem persists, then check the springs for the pressure plate since they could be bad. But my guess is that it's probably your shift lever linkage that's messed up.

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