Mercedes-Benz 300SD One Year Report

After driving my Benz every day for about a year now, I’ve grown accustomed to its spaciousness, toughness, and reliability. Like no other vehicle I’ve driven, this car is truly an engineering success for the folks in Stuttgart. I feel it’s appropriate at this time to mention some of the highlights of my Mercedes-driving experience as well as important to-do items.
  • Listen to your Benz. Over time, you’ll learn to distinguish between the sound of a hot and a cold engine, a wet and a dry engine, an engine that needs oil, coolant, lube, purge, or a valve adjustment. Knowing how your car sounds is pivotal to determining what it needs or will need.
  • Take care of your Benz. Don’t ever skip scheduled maintenance, and the car will thank you by never dying. Well, that’s a stretch, but it will last a really long time. Wash it, lube it, and fix even minor problems. An oil change takes 20 minutes and can be done in Wal-Mart parking lot with some Shell Rotella, a wrench, and a filter; all can be bought at your local AutoZone.
There are certain quirks that can be attributed to this particular model. For instance,
  • The gas pedal might need to be depressed when cold starting. After a few seconds of hovering around 15 on the tachometer, the car will idle normally.
  • The automatic transmission has “sweet spots”. I’ve learned the best places on the tachometer to shift gears by playing with the gas pedal. I know it’s true because when an unaccustomed person drives it, the car shifts like hell – jerking, knocking, etc.
  • The smell of old, moldy ass inside the car can be attributed to rotting foam under the carpeting. Some tell me to grill the carpets in hot sun for a few days, but my mechanic suggested buying a Yankee Candle air freshener. Come one, the car’s over 20 years old, don’t be so picky.
  • The shag carpet will get dirty and you’ll have to steam-clean it on a nice hot day, allowing for plenty of drying time.
  • You will have to plug the car into the grid on cold winter nights. The benefit – almost instantaneous ignition. I wouldn’t keep cranking the starter for more than 10 seconds. If you press gas pedal too hard, you’ll flood the engine with cold diesel fuel. Of yeah, you’ll have to add cetane booster/anti-gel to your fuel.
  • The rear or side air filter housing mount will break due to a design flaw. The engine’s vibrations will always break one of the mounts, so one day your car might shake a bit more than usual.
  • The smell of diesel fuel inside the car can be caused by leaking return lines on valves. Don’t take it to the mechanic, buy some cloth-wrapped lines, pull old lines with needle-nosed pliers, and put new ones on. The last line is a dummy; it’s plugged with a metal pin.
  • The breather hose on top of the air filter housing and valve cover will leak. Don’t worry, it’s normal, just wipe it once in a while.
  • You’ll have to regularly inspect hoses and check for leaks.
  • You will have to adjust valves every 15,000 miles. The process is not complicated, but it takes time. If you get annoyed by doing the adjustment, SELL THE CAR TO SOMEONE WHO WILL APPRECIATE IT.
  • Rear window will probably develop a leak, causing water to sit between layers of glass, in turn causing “fogging”.
  • If your heater starts blowing ice-cold air, replace the monovalve assembly – the rubber membrane tends to break, causing coolant leaks.
  • The car has more power than you think. The "iron five" under its hood doesn’t make it a racer, but the turbo gives it some serious pep. I’ve never had trouble passing anyone on the road. That doesn’t mean a crappy Impala can't kick my ass speed-wise. You will not win any kind of speed trial with this Benz, but you took the reliability/longevity tradeoff when you bought it.
  • The car’s favorite cruising speed is 65 mph. I go 73 on a freeway no problem, but based on the sound and the feel of the car, I have a feeling it “likes” to go 63-65. You must not push it faster than 75. Firstly, there’s no need to go that fast. Secondly, it wasn’t built for speed, so don’t be a dumbass.
  • The electrical items in the interior will break. Over the course of owning this wonderful car, you’ll end up fixing windows, locks, switches, lamps, the odometer, the seats, etc. Those are items with intensive use, so it’s only natural they break.
  • Small mechanical parts will break. You will end up tearing into the doors and wondering why a company as awesome as Mercedes couldn’t make the window slider inside the door out metal. Don’t get pissed off when a $3 white plastic slider ruins your Saturday. But then again, are you man enough to just fix it yourself?
  • If the car is starting to slow down stall and eventually stops like it ran out of fuel, check 1) how much fuel you have 2) the inline fuel filter. Chances are, the little plastic inline filter is plugged up and the engine is not getting enough fuel to burn.
  • If your Benz has an aftermarket alarm installed, get ready for some fun - those alarms are known to go off for no aparent reason after, oh, I don't know, 15-20 years. Disable the alarm by taking out the floor mat on the front passenger's seat, then taking out the carpet, then unhooking the plastic panel way in the back, and finally, by unplugging the sensor.
  • Odometer will break sooner or later. It's weak spot is a pressed-rubber gear that will wear out and fall off, causing your odometer to click. Fix it immediately!

I’ll just keep adding to this list when I think of something new.