It is leaking some dark black oil has 40,000 miles on it

engine oil,every 3to 5 thousand miles depending on what weight oil and brand of oil. transmission fluid, every 45,000 miles 4 wheel drive? change the gear oil in transfer case also every 45,000 miles but i like to insure my vehicles are properly lubed as they are my service trucks also.

At 40K miles it shouldn't burn that much oil, unless the motor has been abused or overheated. With no signs of oil leaks, the engine must be burning it via the exhaust,

Change the oil (use a good quality oil) and then observe oil consumption.

If it still uses excessive oil check further as below:-
1) if it blows blue smoke on steady accelleration (pistons or ring wear),
or
2) only blows blue smoke on initial accelleration after a period of steady coasting or de-celleration (faulty valve stem oil seals).

You need to go to a dealer or a certified mechanic. If you don't know already. Usually these will be the things you have to purchase, plugs, wires, air filter, fuel filter, oil filter & oil, you will need to flush the radiator and the transmission.

Nothing. Assuming you are doing a 5000 mi interval for oil changes, drive happy until 30,000. At that point do the oil, drain water seperator (diesel only) ck washer fluid, ck brakes (mine lasted until 140, 000 mi), depending on your schedule- rotate and balance tires, and check battery. VW also suggests to pop off the timing belt cover and ck for cracks, fluid leaks ect.

Your big service comes at 40,000 mi. Oh, and if you want to take it to a professional shop, save the money and aggravation and go to a local v-dub, or foreign car specialist. Avoid the STEALership at all costs.... this is from a former dealer tech...

It depends on the engine you have. If you do not have a 100,000 mile sparkplug then replace plugs every 40,000 to 50,000 miles. Or at 2 to 3 year intervals whichever comes first.

Other maintenence requires shorter times. Oil changes and filters 3000 to 5000 miles. Air filters about 12,000 miles. If you have a distributor cap and rotor about 30,000 to 40,000 miles depending on wear.
Check antifreeze strength, change antifreeze every 3 years. Always have axles and wheel bearings checked at least every 24,000 miles. Lube door hinges annually, hood release, trunklid hinges, etc.

Try changing oil brands. If you want some good info on oil burnoff rates etc google noac volatility tests.I could explain it here but it would take an hour.
Good luck!

please go to the mercedes dealer and get a service book for that car.
these cars are very car specific and needs to be followed car by car only.
every car is different.
the service needed is not that much right now.
as 40,000 is low miles for this car.
do not go long on the service intervals.
and allways have the engine oil serviced sooner.the cleaner the oil the longer the engine life.
look in the glove box for the owners manuels.
it should be in a black leather binder with a zipper.
all scheduled service is in this leather binder.
if not go right to the dealer and ask them were it is.it very well maybe on the sales reps desk.

hope this helps.
thank you
jm

replacing a thermostat cost about 20 bucks or less done yourself and as far as the oil leak check for loose valv cover bolts and manifold bolts. Dealerships are crooks they will sabotage a vehicle in a heart beat. Try this first.

are u sure it is not comming from up top, the rear mains just don't leak on these engines unless they are very high miles.

1.Check oil level.
2. check oil level
Neon's are bad for having a head oil leak in the first 40,000 to 80,000 miles. Most repair shops wont even tell you if you do have one because they dont want to get invloved, Not enough profit in heavy eng. work