Same here....I can do them all in under an hour...#5 is a little harder to reach, but it doesn't stop me or anything.
I will be replacing them all on my dad's '83 300sd this week, one or more of them have burned out and it starts VERY badly...shakes the car around

Still starts though (even at under 10F), that engine is a beast....
5 brand new Bosch plugs will be used
I agree! Whats up with the low lifespan, we've been only getting around 2 years per set!
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-diesel is not just a fuel, its a way of life-

'15 GLK250 Bluetec 118k - mine - (OC-123,800)
'17 Metris(VITO!) - 37k - wifes (OC-41k)
'09 Sprinter 3500 Winnebago View - 62k (OC - 67k)
'13 ML350 Bluetec - 95k - dad's (OC-98k)
'01 SL500 - 103k(km) - dad's (OC-110,000km)
'16 E400 4matic Sedan - 148k - Brothers (OC-155k)