170k miles G service 200 days over due
I have 185k miles on my 2006 e320 CDI and the cost of routine maintenance is not excessive IMHO. I have replaced the water pump 2 times, glowplugs once, brake reservoir, and one rear axle seal in the past 5 years.
The hours are what it pays according to MB labor rates, they set that and dealers follow it, not the other way around. If you have plugs, a trans service, and some other fluids due, it's easily 5-6 hours at book rate. Most services are actually discounted from the hourly rate, actual repairs are billed at higher $/HR than services normally.


