Factory plugs after 89.9K miles

[Nuke]

I finally got around to changing the stock plugs. Although i hear Toyota recommends changing these copper plugs at 30k miles, I was going to do it at 60k miles (based on past experience with many other cars including 5 other Toyotas) but got sidetracked. Moving 5 times in 6 years, new jobs, new house, yada yada...

Here are pics as they came out: left side/bottom is the passenger side bottom of the pic is the front most plug. Notice the Denso's from the passenger side and NGK's from the driver's side.

I probably could have gone another 60k miles easy...

The passenger side was a cinch. The for driver's side, I had to remove the intake cover, the support bracket between the middle and rear plugs and one end of a hose.

Now to see if my mileage has improved. Tough to tell because some weeks I hardly use the AC and other weeks I may tow more often than the previous. But I have 5 years of data so the next month or 3 should shake out any changes.

 

[JB.]

Thanks for posting.

Very interesting info considering the miles on these plugs.

 

[Nuke]

...Very interesting info considering the miles on these plugs.

Yes, I was quite surprised to see that they were still in decent shape considering the mileage. And the 4Runner was still running great.

 

[BudRunner]

I had the same result with my plugs. Just changed them for the first time since I bought the 4R new back in 2005 with 98,000 on the od.

 

[hearno]

I just changed mine as well at 113k. Guessing the previous owner did them at least once as they looked decent and the rest of the truck was kept up as well. As far as the driver side bank - I got all 3 out with just loosening the support bracket and moving the one hose. It was fairly easy. I noticed a slight bump in mpg. The stock gauge may not be accurate but I'm guessing it's consistent and I am seeing a solid 25 mpg at 65 with the CC set and ac running on a flat road. I used to only see 23 or so on the same stretch under the same conditions.

 

[BlackWorksInc]

Did you measure the gap? I'm curious as to what the wear is, as that's really the main reason they want you replacing them earlier (the iridiums are supposed to last a little longer because they don't devour the tip as fast.)

 

[Nuke]

Did you measure the gap?...

Unfortunately, my old gap tool went no higher than .040. The gap on the new plugs was just barely larger than that .040 and for the comparison, I would take a swag between the new and old and say that the old plugs were pushing .050. I actually bought a new tool today but it's here in the house and the old plugs are in the detached garage about 100 feet away and there are a lot of mosquitoes between here and there. Maybe tomorrow...

 

[Nuke]

Checked gap on the old plugs...

...

After 89,000 miles on the OE copper plugs, the Denso's were at about .055 and the NGK's were at about .060. I wonder if the initial gap was correct on the NGK's to begin with?