How long can you get out of a set of spark plugs.

[super55]

Not sure if this is in the right section but figured since they run off of fuel it would be close enough.

How long can you get out of a set of spark plugs? I know this is going to be an extremely variable answer based on type of engine, carb vs. FI, etc. I was more specifically looking at cars. I have a 2000 silverado and an 06 durango but with between 100-110K miles on them. Both run great and have no reduction in power/fuel economy.

I know for a fact that neither have had the plugs replaced and they are running platinum or iridium plugs. My question is: If the vehicles are running fine is there any real reason to replace them? Changing plugs these days can be a real P.I.T.A on newer cars. I was wondering how long some have gone on a set of plugs before they noticed any reduction in performance.

 

[ray66v]

If you want to avoid potential headaches, replace spark plugs no later than 70K miles.

Leaving them in longer can result in plugs that are seized in the heads. Your not going to save any money if changing them requires major repairs.

I have not seen spark plugs with more than 70K on them that did not have considerable wear on the electrodes.

 

[tcartwri]

If you want to avoid potential headaches, replace spark plugs no later than 70K miles.

Leaving them in longer can result in plugs that are seized in the heads. Your not going to save any money if changing them requires major repairs.

I have not seen spark plugs with more than 70K on them that did not have considerable wear on the electrodes.

X2

Modern efi cars will run until there is almost nothing left of the center electrode.

 

[super55]

The reason I asked this is because I had a trailblazer that I replaced the plugs on when it had 100k. Replaced with Delco platinum plugs just as it had originally came with. (Might have been iridium can't remember) Upon inspection all the plugs were running clean and even after running the feeler gauge on them none of them were more than .008 off from the recommended setting.

AC delco says there platinum plugs are good for a 100k but wondered if they have more life in them after that. I mean they say a oil filter is only good for about 3k miles but most people I know don't change there oil to about 5k now and don't seem to have any issues.

 

[Egon]

See your vehicle manual. It should tell at what milage plugs should be changed at.

 

[Diamondpilot]

I agree with replacing them sooner then later. I have a Titan that recommends 120,000 miles but I will do them at 60,000 and our BMW was just done at 45,000 miles.

Chris

 

[timswi]

I've replaced the plugs in the last 2 GM trucks I've had at 125k ..After removing them, they looked perfect..Since I had them out, I replaced them anyway..

 

[DJ54]

I replaced the plugs in my '96 Z-71 two years ago with 176,000 miles on them. The only reason being, I noticed a slight miss on hills coming back from KY. #8 plug had some buildup on it, but the rest looked good.

 

[catskinner]

170,000 on my 2000 Ranger, original plugs good idea about sticking, I don't plan on changing till it starts running rough.

 

[Bob77064]

On my 2007 Tundra the plugs call for replacement at 100K miles. When I replaced them at close to 91K miles, they looked fine.