With hydro assist available and cheaper than the 105 sector shaft (not so impressive upgrade) I see no reason to buy that over priced sector shaft. i hit my passenger front tire hard enough last year to tear the steering wheel from my grip. the steering wheel was off after that but no twisted splines or failures after a couple hard trails this year. I think it's time for hydro assist anyway.This is true. None were mine, 3 of those were the same guy, although one of those had previously been on my truck (and is the one suspected of being pre-cracked). All of them were hits to the passenger side wheel, on trails. What's concerning is that the comment 'I didn't think I hit it that hard' is common. Of course, hitting an immovable object at 10 mph might not seem like 'that hard' but stopping 3 tons of anything moving at any speed instantly takes a lot of force.
Also, with an improved sector shaft in place, I don't know what becomes the 'fuse' in the system. Probably the steering arm.