Most Miles till Spark Plug change?

Went by Toyota Service to buy the correct plugs and they told me if it wasn't missing I would be waisting my money...hold off on changing them until I could feel a noticable miss or received a code. Mileage is at 20mpg if I am in a hurry to get there...22 if I take my time and stay off the interstate. I am going to change them soon and see if it makes a difference.

 

Did 2000's come with platinum's stock? I really don't know....but Gen 2's (4L engines) come with copper plugs stock. They generally don't last as long as plat's or, especially, iridium's.

 

Bogus advice! All the plugs are wearing and waiting till one wears so bad it misfires is just bad practice for fuel economy, engine performance and worse is potentially VERY, VERY costly!

Unburned fuel entering the cat's poisons them quickly...have you priced new catalytic converters?

 

^^^ I just did mine recently at 50k and they looked just about exactly the same. I just got new plugs from toyota, was told you dont need anything more really.

 

well i just changed mine yesterday and i had ngk's on one side and densos on the other side so that means they are factory and my truck has 91,000 on it so thats alot

 

Changed my yesterday, really pretty easy if you follow directions. I bought my 05 DCLB 4X4 with 116,000 miles on it, now has 123,000. I am pretty sure that the plugs had never been changed before. Denso's came out of the passenger side and had a gap of about .058. NGK's came out of the drivers side and had gaps of .068+. The Denso's definately looked like they held up better over time. The prong on the NGK's were worn pretty thin as was the electrode.

We will see if it improves my mileage or driveability. I never noticed that the truck was running poorly before I changed them. And surprise, surprise the dealer was the cheapest place I could find to buy em. They came pre gapped at .040 from the dealer and yes I did check them!

 

Changed mine at 90k.

 

changed mine at 178k

 

According to the service records the plugs on my current 4.0 truck were changed at 102k miles for the first time. On my last 05 which was a 2.7 I changed them at 100k and they looked perfectly fine. But they are iridiums stock.

 

128,000 gap was .061 I am going 30K now, They're EZ to change.

 

Of all the maintenance items that are recommended at 30K, I think the spark plugs are probably not as critical compared to everything else.

On my 96 tacoma, I bought it used (at 60k) and I changed the plugs at 80k miles. I know for a fact, they were original plugs. They were worn pretty good....but I never saw any performance issues.

My mother-in-laws Grand Cherokee has 80k miles on it and I doubt the plugs were ever changed. It is starting to act funny (so she tells us). That'll be something we'll have to do this summer.

I just bought a set of plugs from the dealer for my truck.....(32k miles). I hope to change them out this summer. If time is short, I won't be worried about it.

 

I just changed the OEM (DENSO) plugs on my '05 4.0L V6 at 96,000 and they looked fine. The gaps measured about 0.045". The OWNER'S MANUAL calls for 0.043. There's probably some electrode erosion going on that opened up the gaps, but there was no evidence of oil or carbon fouling.

The SCHEDULED MAINTENANCE GUIDE (which is what the dealers go by) calls for spark plug replacement at 90,000 to maintain the emission system warranty. Because I found electrode erosion on the old plugs, I installed NGK IRIDIUMS which are rated to last 150,000, although I'll probably change them at around 200,000. So unless you've got an oil or carbon fouling problem, your plugs will last a lot of miles.