OverlanderJK
Resident Smartass
PR44 vs PR60? I've done both.
Back in 2010 I installed a 2.5" Teraflex lift, 35s, and a PR44 w/ 5.38 gears in a two door JK. Unfortunately I had a pretty bad front driveline vibration, that after all was said and done, proved to be very difficult to cure. I adjusted the pinion angle more times than I could count, going all the way from obviously too high, to obviously too low, in 1/2 degree increments, with no success. I rebalanced the Tom Wood driveshaft, with no improvement. I had another driveshaft made, with no improvement. Then rebalanced the new driveshaft, with no improvement. I rotated the tires, balanced the tires (twice), and even bought a new set of tires, which didn't help. I changed front axle shafts, which didn't help either. I never did totally fix that driveline vibration, but if I removed the front driveshaft it was gone. About that time I said to myself "self, never again will I spend the money on a new axle, and buy an axle that doesn't have locking hubs".
Fast foward to 2014, and I'm building another two door JK. This time I used a 3" Teraflex lift, 37s, and PR60s with 4.56 gears, and front locking hubs. And this time the Jeep is as smooth as silk. Not only is it smooth, its the smoothest Jeep I've ever owned. There is less driveline vibration than is typically present in even an entirely stock JK. This JK drives wonderfully, and I'm so glad I went with the PR60 this time. I'm sure the 4.56 gears vs 5.38 gears is part of the smoothness, because driveshaft RPM is much less with the 4.56 gears, but being able to unlock the front end on the highway is a huge advantage.
Anyway, just my experiences. Good luck with whatever you choose.
Your issue was probably had to do with the 5.38's. Why on earth would you do 4.56 with 37's and 60's?