i think it has to do with how securly they are mounted, if they are bouncing around all the time they will burn out faster, whereas if they are mounted well they shouldnt move around as much. maybe the post 98s had some problems in that area.
1994 Volvo 850 Turbo
1992 Bronco Eddie Bauer 5.8 E4OD
1998 Contour GL 2.5 CD4E
2001 Montero Sport Limited 3.5 Auto
2002 IS300 3.0 Auto
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