Talking about the front here: I've been reading old threads for a half hour and can't seem to get a definitive answer. Yes, I know it's recommended, but is it 100% needed? Also, when it fails, is it catastrophic, or will a vibration get progressively worse? And yes, I'm being cheap. I paid $500 for it, LOL.

 

The stock driveshaft is pretty strong, but you're problem is going to come from the fact that the stock driveshaft doesn't have greasable u-joints, and this is a problem regardless of the lift. If you don't rebuild it with greasable joints (and remember to grease them!) or get a heavier duty DS, then the driveshaft will eventually knock a hole in the transmission.

 

Okay that makes sense. Is the Lucky8 one good enough you think?

 

Lucky8 have those and the heavy duty ones they sell are Tom Woods. A lot easier to grease beause the points are at the end of the bearing not in the middle where you can hardly reach.

 

I'm on 3.5" lift with the lucky 8 shaft. No complaints thus far.