Greetings. After viewing forum for last 6 months and learning a lot I need some advice. Purchased 91 350SD 2.5 years ago with 106K miles. Great car, I hope. Read about rod bender on forum. Started researching. From warranty records at Mercedes, I know in 1993 a rod broke with 38K miles. Can't find out if rebuilt or shortblock was installed at Florida dealer. My local KY dealer service man says he is confident what mercedes did was install new shortblock. I know a new engine was not install because engine number at top still matches original papers.
The second day I owned the car I drove it straight through 600 miles to visit family, 70-75 mph. Noticed oil consumption, 3/4 quart.
Last month with 147K miles (40K miles later) that same 600 mile trip (70-75 mph)resulted in one qt oil consumption. However, I notice it smokes more in last 6 months...blue is color. No oil leaks. I use Shell Rotella T 15W-40, change every 5K miles.
Driving locally I seem to go 800 miles on qt of oil.
Discussed issued with my local dealer he said at 1 qt consumption at 500 miles he recommends I bring it in...he says could be valves seals/ guides.
I read the forum about oil consumption test, compression tests, oil analysis tests. If rods are bending again, would the oil analysis pick up metals in oil? I guess I need some advice on whether any tests would give me piece of mind. In the meantime I drive it a lot on trips, 75mph, what a great ride! Mileage is always in 24-26 mpg range. Drives today like it did 2.5 years ago, seems to have great power, but this is my first diesel. I getting ready to drive on another 600 miles one-way trip, am I pushing my luck? Any advice is greatly appreciated!
JT