Bay Leaf

Hi I have a SL 350 2013 model and I'm having difficulty finding out at what milage the spark plugs should be changed.
Any ideas anyone please.

hornethandler

This should help (2013_Passender-Cars_Service).

hornethandler

Been trying to upload the pdf file but it wont go.
I'll try again here...

rmorin49

Don't know what MB recommends but running high quality non-leaded gas and regular oil changes, plugs should easily last 50k miles. My wife's RX just turned over 100k miles with the original plugs. Runs like new.
I may change my SL plugs at 50k miles.

hornethandler

According to the 2013 service booklet (the one I posted above) the SL plugs are changed at 100,000KM or 4 Yrs.

rmorin49

Interesting. Don't know why time is a factor. Plugs unused shouldn't deteriorate. I'll agree on mileage.

hornethandler

I just found a booklet for a 2017 SL. It's still @ 100,000KM, but 6 yrs instead of 4.
Just a SWAG... but depending on the material used, perhaps leaving them in too long makes them harder to get out because of corrosion???

JettaRed

iTrader: (1)

Hmmm, that's an interesting theory. The plugs are iridium and should easily last 100,000 miles, but the 2015 Maintenance Booklet says 46,500, so that's what I do. MOST importantly is to get the right plug and install it correctly, indexed to the fuel injector (torqued to 23 Nm using genuine plugs). Honestly, I agree with @rmorin49 that the time thing is perplexing.