My sons truck broke the snout off of the crankshaft. That being said we pulled the trans and droped the crank out to replace it. While the trans is out I replaced the trans flilter. When removing the old filter one of the bolts had a nut on the end of it(trans is upside down) insead of a tapped hole like the rest of the bolt holes. My question: Is this the way it came from Mazda? Did this bolt/nut combo have a lock washer on it (I can't find one if it did)? Thank God I was able to see the nut and remove it. Thanks.

 

Most likely some fool at a jiffy lube stripped it off years ago and the fit a stud in it or something. I've never been into the automatic to know for sure but it doesn't sound normal.

Breaking the snout off the crankshaft is a common problem that is likely the result of a severe torque spec typo in the Haynes and Chiltons manuals. To make sure this doesn't happen again make sure the 21 mm bolt in the center of the crank pulley is torqued to the factory spec of 116-123 lb/ft