ps2cho

So I stopped by dealer and they said car needs spark plugs at 106k. I go home and manual from mb website says 91k.

Which is it?
2008 e350 4matic

Car has 103k hence I don't want to replace something that was just replaced...was he just mistaken?

konigstiger

MB: 91,000 or 5 years (whichever comes first)

ps2cho

That's what I thought...he must have been mistaken.

Interesting it states trans fluid change only once at 39k with no more.

I'll do it again thanks mb. I should be OK to do another with me at 104k now right?

konigstiger

09 MB changed requirement to every 40,000 miles/4-years for ATF and transfer case oil (4matic).

Wodeshed

Just wondering...what goes wrong with plugs in an older but still very low mileage car? I'm planning to replace mine in a newly acquired 07 E350 that only has 32k miles, but I'm still wondering why the age guidance for replacement?

vettdvr

Plugs don't go bad in the box or in your engine when not running.

However it is possible for the plug thread to seize in the head and pull the threads out with the plug. I changed mine early just to be sure they didn't seize. I could have put them back but that didn't seem like the right approach so I put in new Bosch. And yes against everyone who said put them dry I used spark plug anti-seize .

Wodeshed

That's what I suspected. I think I may remove and inspect mine, and if they're still looking good maybe put 'em back in. My car was obviously garaged since it still looks and smells new inside, outside, and even underneath. I did take a look at the Navigation history, and it looks like it was used to go from the retirement community (probably advertised on your local TV stations) to the nearest mall and back.

konigstiger

FYI

Hsg08

My dd 07 E350 just hit 115k miles. I havent changed my spark plugs yet since the car still idles pretty good and no bad plugs signs/symptoms. Should i replace all of them anyway? Thanks

ezshift5

......spark plugs have come a LONG way.......

For example: the Iridum plug. At circa 145k, my NSX 3.2 liter V6 shows little degradation from the usual benchmarks.....(starting, idle, MPG, missing on hard acceleration).

ez

vettdvr

Yes I put the dielectric grease on each plug wire cap to seal out moisture and make it easier to remove. Good point.

vettdvr

The plugs in my airplane engine also last a long time however the resistor internally can break down/open and the plug still fire. This causes current to be too high in the circuit leading to other failures.

The same can happen in a car engine.