Originally posted by Christian
So are you all saying that a V8 would definately last longer than a 4-cyl? Or will a well kept 4-Cyl last a long time without a major overhaul
That's like asking "how long is a piece of string?"
Depends. There is some thought that the need for a four-banger to rev to make power would mean earlier wear. There is also thought that due to their smaller displacement, they are higher stressed and therefore wear out earlier.
I'm not familiar with the smaller displcement four-cylinder engines found in the C-Class, as they were not offered here. Is your engine an M111 DOHC family member? If so, you've happened onto a good engine.
I have several friends with very many miles on their M111, and the engines are proving to be very strong. The following are things that will extend the life of any engine:
1. Change the oil and filter often.
2. Use synthetic oil, especially if you live where temperatures get cold.
3. Be very gentle on your engine after a cold start. Wait for the engine to warm (not just until coolant is at 80) completely before high revving or loading it up.
4. Don't drive like Tommie on rally-day.
5. Keep things like fuel filters and air filters fresh.
By following these practices, I've had several M102 (early 8V 190E four cylinder) engines still strong at 400,000 kilometers (250K-miles).
Most MB engines, whether 4, 6, or 8 cylinders, will outlast the automatic tranny it's bolted to.