My 2013 Accent GS had an internal shaft punch a hole in the casing at around 120,000 miles. My mechanic said he's never seen that before. I had a used one with 15,000 miles put in, and now, 120,000 miles later, the case has a crack in it. What gives? Anyone else had anything like this happen?
Despite this, I still love the car, I can get upwards of 40mpg with 260k miles on it if I take it easy, though I rarely do. I think it looks more modern and sleek inside than the Nissans and Toyotas I've rented recently, which look like 1980s styling with an infotainment screen pasted on the dash.
I guess I should be glad Hyundai no longer makes hatchbacks, because I'd have bought a new one before this happened.

 

In reading your post, I believe you answered your own concern.

Grant you, some components can and will take considerable abuse, but it is only a small gearbox made to do a certain job and typical use usually will provide satisfactory service.
. It most likely is responding to the demands you might be placing on the unit.
Do you think you might be able to alter your ,"Rarely take it easy" procedure and drive it as it was intended to be driven? Probably would save you a lot of $$$,.