I do mine at or before 15k, 30k's acceptable, 10k's obsessive.
If I had to change every 15k I would think something was seriously wrong with the engine, even 15k seems obsessive if your engine is doing fine. I guess if you say seafoam once a year this would make sense.
When you know, you know. You know?
I am currently at 43,000 without changing them. Not having any issues but was thinking they should be done soon. I have heard a lot of opinions from different people so I wanted to see what other liberty drivers were doing.
Not all shops have parts installers. I gap all the plugs I install, I can promise you that. I do know plenty of slackers though that dont do the work right, and I get brought in to clean up their mess. Every 30k is what the manual says, and they typically are pretty worn by that point. Its maint. work, so you want to do it before you start having problems. Its easy to do, so if you can handle it, do it yourself. Back just 20 years ago, alot of vehicles still needed plugs every 15k, so it really isnt beyond reasonable. We have all just grown to believe cars go forever.
i've pulled plugs out of some of those "100k" mile vehicles at 60K and they looked more like ceramic glow plugs at that point
spark plugs are a prime example of declining return on investment
you put in a new plug, and every time it fires, heats up, cools down, it degrades, they don't magically peter out at 30k, 60k, 100k.. or whatever, they slowly degrade. So slowly that most drivers never notice it until they notice something else
A misfire, poor gas mileage, poor performance - and many of them rack it up to . Oh.. well it's getting some age on it
the bosch on the left has less than 40k on it and it was missing +20% of it's electrodes
Plugs on the right had about 96k on them - I was surprised they even fired
I take that back, they weren't firing, the dealer had been charging them diagnostic fees because the engine kept going into safe mode for the last 30k miles with no resolution to the problem and I almost couldn't get the plugs out of the head - had to freeze the plug to get it out
For the cost of the plugs.. it's inane to run them till they literally quit firing
add on top of that.. can't tell you how many plugs I've seen seized in the head after being in there over 60k
Spend the 20 bucks.. or 50 .. or whatever you want to spend, and change the plugs at or under 30k
Got 62,000 miles on my 2006.
I have cleaned the plugs once at about 45,000 miles and they didn't look bad at the time. I'm leaving them in for as long as they work properly and the fuel mileage does not suffer. When it starts to stumble or the mileage goes down I can spend the 40 minutes and change them.
(Note: I have converted my numbers to miles)
Last edited by Clockworkorange; 09-09-2011 at 12:00 PM..
Reason: last line
it really is simple to change plugs on this vehicle, i believe there are a couple youtube vids showing how to do it...rear passenger is the hardest, and as someone said it simply requires pulling the coolant tub which has 2 screws...
You guys that want to wait until it starts to run bad, do you know how much the computer will compensate to keep it running, before you will see changes? How much do cats cost, and do you know what causes them to melt down? Plugs are sure cheap to change when your supposed to!