hey ive got a 2005 navara d22 3.0litre turbo diesel has done 110000 ks.i took my car into Nissan for the front crank seal to be changed. i got a phone call from them saying they cant tighten the crank nut and when they do it locks the engine up, so the crank pulley is floating around. they told me it needed to be stripped to find out whats wrong. i just want some info and what u guys think it could be as it could be very costly cheers guys and happy new year in (few days)