GLguy

I am approaching 70K and 10-year interval and plan to replace spark plugs and air filters. Is there anything else I should do while the top of the engine if off? Any seals, caps, etc? Items which are not listed in the service manual but might be a good idea to replace after 10 years. This is for 2009 GL 450.

Thanks.

kombifan

DrMel

I was always taught to replace the coils with plugs but that was when I worked on american muscle. Is that necessary for MB's? I'm at 120K miles. I see fcpeuro has a kit that includes coils which by the way is still cheaper than what the dealer quoted me.

-Mel

fabbrisd1

Coils and wires are not "required" time/mileage for replacement - and are generally replaced if you have specific misfire codes.

Spark plugs - genuine OE equivalent only - don't get sucked in by other pizzaz/hyped plugs.

At 120K/10yrs - if I was doing spark plug job - I would choose to do fresh geneuine Bosch MAF from a reputable seller (like $85-$90) - MAF will ultimately go out-of-normal range and give you CEL - fresh MAF will give you original factory new spec and best fuel economy and performance - up in the engine compartment I would also do fresh coolant change - MB coolant or Zerex/Valvoline G05 only - if mixing concentrate use distilled water only - to bring cooling system back to neutral ph to prevent internal corrosion due to dis-similar metals/hydrolysis.

At 120K/10yrs - I would seriously do tranny fluid change - correct filter - correct fluid - and medical precision correct procedure. Tranny service is key to run up to 200K mark

lkchris

Yes ... and YR7MPP33 and Y7MPP33 are NOT the same thing. The car did not come with resistor plugs, you don't need resistor plugs, and you shouldn't use resistor plugs. Order correct plugs from Mercedes dealer.

Mikchek

my dealer quoted me like $20 for a plug

eric_in_sd

I did a little research on resistor plugs. Conclusion was that the resistors in the Bosch plugs don't make a difference.

DrMel

I was hoping to hear this. I literally just ordered a set of the resistor plugs from fcpeuro two days ago, not knowing they were any different since they push those as being OEM... I've read alot of reviews on Amazon from MB owners who say the plugs work great.

BlownV8

I replaced the plug wires and coil packs while I was in there. The coil packs and wires are very inexpensive if you buy them online.

fkong777

I did plugs, air mass sensor and air filter. I couldn't even find the crank position sensor or I would have done that too. Actually since my ECM was messed up and got a reman ECM from the dealer installed at $2000. Im thinking I will lay down a heat barrier mat under the ECM to minimize heat.