I think the greatest benefit for iridium plugs does not apply to the LR2. It's most appreciated for V-engines where one bank of plugs is blocked by the intake manifold and it's a half-day project to get the manifold off and back on, and hope you don't break anything in the process. Since iridium plugs don't need to be changed as often, it's a less frequent hassle.

 

Hi LR2driver - you are dead right - overall a POS job although with chevy V8 you do have (crappy) access to all the plugs (Landcruiser 4.7 V8 was easier than the chevy for sure) - 4 more plugs to get in now & job done - so fingers crossed for no x/threading. I had read reports of Iridium plugs in the Yukon (Chevy V8) lasting 200k miles - I was not having any issues - hence why I let it run for so long.... I have replaced the plugs with Bosch double tipped iridium based on performance of original iridium plugs. Could be the last set of plugs this vehicle/engine will see. Hoping for 250k miles - essentially another 5 years at 10k miles per year (For flybd5 - dont worry, I was much more fastidious about the fluid regimes than the plugs )