sound metal grinding on 1994 Nissan Pickup (D21)

hi! i got a 94 nissan hardbody 4cylinder manual. i used 1,2,3 and 5th gear u can hear sound like a grinding metal but if i shift to 4th gear hear nothing, what's wrong with my truck?

Asked by for the 1994 Nissan Pickup (D21)
I think your transmission bearings are failing. It will require an overhaul to fix it.
Get to a Nissan specialist or a transmission shop for an estimate.
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