Has anyone performed this on a 2011 XJL Supercharged? Considering doing this myself. RockAuto has the pump for about $85. Note: engine has been emitting a "metal on metal" sound for a little while now. Took a look at pulley and watched it quickly shift (lean forward) and shift back while spinning. I thought I was seeing things until I watched it do it again 20 seconds later! No overheating but very slight smell. I've got about 65 miles on the car so out of warranty. Any use in calling Jag Corporate? I hear the service can be over $1,800!!!