Spark plug replacement

[T4Rscott]

Hi all,

I have a 99 4R with the 3.4L.

I the last five years, I’ve only averaged about 8-9,000 miles per year, some cases a lot less!

The last time I replaced my plugs, it was at 214k back in Sept of 2019. Here it is Nov. 2021 and I’m at almost 227,000 miles.

Should I replace my plugs? Are there any concerns as to the plugs getting stuck in the head when left too long? I do a very light application of anti- seize when replacing them. I also idle longer than I should.

The truck runs well and mileage is on par. I know the interval is 30,000 miles. However, at the rate I’m going, it’ll probably take another year and a half to get to 30k.

All the best,
Scott

 

[jgue467]

If it starts easy cold or hot and fuel mileage is satisfactory, I'd leave them alone until they reach 30K. Even then you can pull one or two to check their condition before deciding to replace, they aren't cheap anymore.

 

[T4Rscott]

It starts fine cold. Hot, it has always had a slight stumble on start up no matter the age of the plugs

 

[pluton]

Since you installed the plugs, and therefore you know it was done correctly, I think you're safe for another year. I replace mine every 2 years (just prior to our beloved biannual CA emissions testing) but, based on their appearance, they could easily go longer than 2 years.