I need to pull my Dorman and check it. I have about 1000 miles on it now. The dorman does get lube to the top bushing in the form of oil vapor. A bronze bushing does not take too much oil to stay alive. You figure the OPDA shaft spins between 1000 and 2000 and spins about 1500 at cruising speed. And has about zero load to boot. As far as the bottom bushing wallowing out, that is totally a alignment issue. The bottom bushing takes the brunt of the force from the oil pump load. The stock units once worn are shot for alignment and getting the SG modded units in proper alignment is impossible as I have found out. You also get more side load on the shaft gear if the gears are worn. The only true method to fix this for good would be to change the cam shaft along with the OPDA and even then you may have a bad engine block casting that does not allow proper gear clearance. I think constant monitoring of this OPDA is in order. I'd have no issue pulling the thing every 5-10K miles and checking it. It's just what needs to happen if you own a newer 4.0 Jeep.
2006 Solar Yellow Rubicon Unlimited
Jeep Club Member #1340
6 Speed, Hardtop
Mods done: Hurst tee handle, cheap hand throttle, Rokmen Merc front bumper, Warn 9.5 TI winch with 3/8" X 100 worth of Viking yellow rope, DPG OME Ultimate with JKS ACOS up front, Kilby Gas Tank Skid, Kilby Steering Box Skid, Jeep Medic Belly Up, Skidrow Engine Skid, Rockcrusher Diff Skid in the rear, Warn Diff cover in front, , AR Outlaw II's and MTR 12:50/15's, Homemade rear Bumper, Cheap Cobra CB, Puma OBA, Sirius Radio, Locker Defeat, Rockhard cage, Rockmen short corners, homemade tire swing/tailgate hinge affair, Airlift air bags on the rear- - - - - - and more to come!