91 Trooper II Clutch

[BlakeTN]

I have a 91 Trooper II 4X4 with a bad clutch problem and the autorepair doesn't know what is going on with it.
The clutch keeps shattering or at least that is what the repair guys say.
The first time they replaced it they left of the dampener after 94 miles it shattered again, under warranty so they replaced it. after 2 weeks and another 90+ miles it shattered again but I noticed a tightness when I shifted from 1st to 2nd, told them they said that was normal. Once again while in line at a drive thru it shattered again. The warranty guy says he has only seen this when someone is racing and riding the clutch hard. I'm 38 and it's an Isuzu, so no racing on my part. The repair guys stated they have checked everything out and can not find a reason for it. They have currently had the thing for a month now. Does anyone know what the problem may be?