Once I had the driveshaft down, I went around and checked all the u-joints for smoothness/movement. it was obvious that something was wrong when I got to that one. it's the only one bad.
This driveshaft has the Spicer 1330 u-joints. The ones I installed did not have grease fittings. Perhaps if I had grease fittings I would have seen the wear/movement while greasing.
I've been considering another mod - but I'll post new.
-Mike
1982 F250 4x4 XLT Lariat, 460cid, 9.5:1, TFS 290 Street Port heads, Crane Hyd. Roller cam (278/286 adv.,216/224 @.050, .560"/.586" lift), Edelbrock Performer 460 intake, MSD Atomic TBI fuel injection, MSD 6AL ignition, MSD Billet distrib., Hedman headers, NOS Cheater system, 4" Suspension lift, 3" body lift, 4.56 gearing, 17x12.5Rx37 tires MT Baja ATZ-P3.