Shattered 4R100 Thrust Bearing- Anyone Seen This?

[SirZoltun]

Hey guys!

I have an early 1999 F250 Superduty. 7.3L Turbo Diesel, 4R100, I-Beam 2WD. Front end lifted, 35" tires. 1-piece driveshaft w/ 3.73 rear end. 280,000 miles (trans rebuilt by Ford before I owned it at 245,000). Never had a problem til today.

Tore it down and when I got to the rear housing I found that the #13 thrust bearing (between the case and the park gear) and thrust plate are destroyed! The rear of the transmission case is ruined where the park gear ground at it; both will need replaced. Ugh.....

I was wondering if anyone has seen a shattered thrust bearing in a transmission before? It broke into five pieces and fell into the rear housing. The thrust bearing is still there, but the rollers fell out. Any idea what caused it? Could this be caused by a driveshaft problem? Maybe some sort of drivetrain problem?

Thanks for any help, I appriciate it!