By the way, is it a common occurrence for the self tapping screws to fall out of the torque bracket on the front of the transaxle? From what I can see, the holes are stripped. Is there any way to repair something like this, or at least prevent it from happening again?
Yes
It is one of the things that good techs check when they service a mower
Your owners manual will simply say "check all fasteners" which really means nothing to most people
But torque straps & engine mounts always need checking because they do work loose.
A little BLUE loctite will usually stop bad ones that come loose regularly
However if you do that go up to grade 8 bolts because it is not uncommon to find the heads sheared off
The problem is in the actual frames that are too thin ( and getting thinner ) .
Most were designed when 10Hp was a big engine and 40" was a big deck
Well engines get more powerful every season & decks just get keep on growing + they bag or mulch.
All of this puts a lot of stress on the frame
The Husqvarna frame regularly cracks ( most don't notice them happening ) and in particular the deck hangers which I regularly weld & add patch plates to .
There is a good reason why real commercial quality mowers are 3 to 5 times the price of the domestic grade mowers .
As one of my fellow techs used to say when asked about what mowers to buy
"Do you want a mower that will last a life time & do the job properly or one that looks pretty in your garage ?"