One problem related to infant child seat handle has been reported for the 1998 GMC Sierra. The most recently reported issues are listed below.
When applying the brakes in a sudden stop, the middle lap seat belt did not lock, causing passenger to move forward near the dash area. Also, car seat in middle rear belt, doesn't lock, causing car seat to fall over, resulting in 2-year old hitting his head. Abs brakes fail, fad eon some stops, will not stop.