Just wondering why we feel the need to change irridium plugs in the 90 K service. Okay if you have plenty of money, but if you do the servicing yourself afer the warranty has already run out! and will have no bearing on future repairs, why bother. I for one won't be, My reasons are mainly cause I have driven my 93 Vienta 365K before I sold it and the plugs were original. Then My 2004 V6 Altise 290 K without replacing them either. Now I have just replaced My 94 NJ Pajero V6 plugs! which are the normal standard plugs, after they had done 161,000 Km on a 309K motor! I replaced them imediately after I noticed a stutter on acceleration with a load. Slack you might think but even standard plugs last for a long time these days as it was Lead deposits! then Lead Replacement petrol which killed plugs in the first place by eating them away. If you think about it a single plug failure will not leave you stranded and will easily get you home hundreds of miles, un like other electrical componants that will leave you stranded. EG: Battery. Fuel Pump. Starter Motor even Alternator after a short while will leave you and your family stranded and these more critical componants aren't on a replacement schedule, only as they fail are they replaced. Just something to think about if you wanted to save some money on the do it yourself schedule. Sure the plugs might be harder to get out eventually! I put anti seize on the replacement Pajero plugs but one was cross threaded by I imagine the Dealer and is still in there as it will not move much with out locking up but runs idles well with it still in. But I don't feel the need to bust the spark plug and spend hours on a car that in the long run will not be worth the effort dollar wise it just tows the boat to the Ramp. However Oil / Filter Transmission, timing belt etc I have always been fasidious with as that will have an impact on the life of your engine and or catastrophic engine failure. Just don't feel the need with the plugs as a failure will not be critical or effect the life of the motor. Cheers