Spark plug change

No iridium plugs in the 4.0, I did my plugs @ 31k with OEM Denso's from the dealer. cheap & easy. Didn't notice a change in performance,MPG etc. but I feel better following the required maint schedule and it gave me an excuse to work on the truck.

 

2.7 liter = iridium plugs

4.0 liter = plain copper plugs ( even the newer ones )

 

I just took the old plugs back to Advance Auto Parts. He checked the part number, they are Denso double platinum plugs. These needed to be changed every 30 thousand?

 

Just changed mine in my 08 TRD Taco Sport 4X4 a week ago. My manual said the V6 came with 60k plugs.....not true. Mine came with the same as everyone else's, half NGK V groove copper tops, half Denso U groove copper tops. They are supposed to be a 30k plug max. I put over 63K on them, they were badly wore and the truck was pinging. So I put in the NGK Iridium's, It now runs like silk, and pings no more. Overall power is up as is my gas mileage. Sure wish it was as easy as it used to be in the good old days. Those individual coils cost over 80 bucks a piece, I hope they last? Rick