Spark Plug Change

[roadsession]

Hello,
Any thoughts on:

(A)
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When spark plugs should be replaced on a 99ML320 ( I have 62K miles), and is it a DIY job, and if so, any idea on the torque that needs to be applied on the plugs?

(B)
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Also, I have a 97 C230 that I am going to change plugs on. Any ideas on what the torque setting for the plugs on that car is?

(C)
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Also, I'm buying the plugs thru fastlane. Are they already pre-gapped or do I have to adjust gaps. If so, what's the gap setting?

Thanks!

[pmount]

I just changed plugs on 1998 ML320. I removed the frt wheels and the inner fender liner on both sides and it was an easy job. Replaced the frt pads also while wheels were off. you will get many answers on when to change them. I think time could be as important as miles. Also. one small exhaust shield needs to be removed on the drivers side. This is all easier than it sounds. I don't think my 1998 E320 wagon will be this easy. The ML had 89,000 miles. Good luck.