I've been wondering about break-in on the engine. I'm 1,200 miles away and it's interstate home. Is break-in still a thing or has that rule passed?
The only break-in has to do with towing. Owners manual says no towing for first 500 miles, then 500 miles of towing under 50mph. Last year I took a couple of day trips with the wife pulling the 5er off of the interstate. It has nothing to do with the engine, but the transmission, driveline, rear-end, etc...something to do with seating everything.
From the manual:
The Cummins® Turbo Diesel engine does not require a break-in period due to its construction. Normal operation is allowed, providing the following recommendations are followed:
- Warm up the engine before placing it under load.
- Do not operate the engine at idle for prolonged periods.
- Use the appropriate transmission gear to prevent engine lugging.
- Observe vehicle oil pressure and temperature indicators.
- Check the coolant and oil levels frequently.
- Vary throttle position at highway speeds when carrying or towing significant weight.
- Do not tow a trailer at all during the first 500 miles (805 km) the new vehicle is driven. The engine, axle or other parts could be damaged.
- Then, during the first 500 miles (805 km) that a trailer is towed, do not drive over 50 mph (80 km/h) and do not make starts at full throttle. This helps the engine and other parts of the vehicle wear in at the heavier loads.
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