There are not many warning signs of an impending ims failure short of a death rattle that occurs as the bearing fails and comes apart. These kits replace the factory sealed bearing with a new, severe duty custom ceramic hybrid roller ball bearing for reduced friction and superior performance in poorly lubricated operating conditions and replaces the factory ims flange hub, bearing support, and fastener with a stronger, revised billet chromoly assembly. The center bearing support also receives an increase in size and no longer is cut for the o-ring that keep engine oil from leaking out of the engine - we have relocated the o-ring to the ims hub flange for added strength to the center stud & bearing support. If doing a rear main seal (rms), it s recommended to do an ims retrofit at the same time, as the majority of the labor is identical to that of performing the rms service. Note: all 1997-99 vehicles with their original engines will require a dual row retrofit kit. 2000-01 vehicles may need either a dual row or single row retrofit kit, so you ll need to inspect the flange, as described below to be sure which will be needed. 2002-05 will need a single row retrofit kit, although depending on how late the build date was, there may be some 2005 vehicles with the updated m97 ims, which is not serviceable, at least without teardown of the engine.