I can count, on one hand, the number of times I let my car go more than 2,200 miles without an oil change and filter. Maybe it's overkill, but I haven't had any major engine issue yet, other than the ongoing need for valve seals. I read that the 119 engine is one of the more unforgiving engines for long oil change intervals.

I was looking at doing the valve seals and timing chain myself, but I would need over $700 in tools and I'm not sure I want to risk not getting the four cams lined back up correctly. Other posters have recommended that this is a tough DIY job to tackle unless you've seen someone with experience do it before.

I am thinking about pulling the heads off myself, taking them to a good machine shop (someone that knows MB), and then towing my car to a tech when the heads are finished, so I can watch him torque them back on and get the cams installed correctly. I would probably tow it back home afterwards and do the remaining work. That way, I wouldn't have to worry about buying or renting the special tools and I wouldn't have to worry as much when it came time to turn the key.

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1993 400E, 256,000 miles (totaled)
1994 E420, 200,000+ miles
1995 E420, 201,000 miles