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- Dec 30, 2022
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Article is three years old but this stuck out to me:
Straight out of the gate we recommend 6000 km (3700 mile) oil changes if you are running conventional oil 15W/40. This should be a safe interval for city driving, stop and go driving, and idling. Some vehicles can get away with a 8000 km (5000 miles) stretch if you are mostly doing highway driving, consistently long trips where the engine can get nice and warm and run for extended periods.
running past these distances can really put your engine at risk of damage from a buildup of sludge and soot. For the skeptic that reads this article and drives by his oil change reminder message that pops up in the dash, an important point to know is that the message is triggered by restriction across the filter and / or engine run time, it doesn’t actually monitor oil degradation. The older Cummins powered trucks ran cool, clean intake air and the recommended oil change was 6000 kms (3700 miles). A 6.7 engine doesn’t filter any better, doesn’t hold any more oil, burns more fuel, plus it runs way hotter and dirtier internally, yet the manufacturer has increased the oil change interval recommendation. To us that doesn’t make sense and is evidenced by catastrophic engine failures we have seen in our shop.
Not sure what to think, the norm on these engines seems to be 10k miles
xlmechanicalservice.ca
Straight out of the gate we recommend 6000 km (3700 mile) oil changes if you are running conventional oil 15W/40. This should be a safe interval for city driving, stop and go driving, and idling. Some vehicles can get away with a 8000 km (5000 miles) stretch if you are mostly doing highway driving, consistently long trips where the engine can get nice and warm and run for extended periods.
running past these distances can really put your engine at risk of damage from a buildup of sludge and soot. For the skeptic that reads this article and drives by his oil change reminder message that pops up in the dash, an important point to know is that the message is triggered by restriction across the filter and / or engine run time, it doesn’t actually monitor oil degradation. The older Cummins powered trucks ran cool, clean intake air and the recommended oil change was 6000 kms (3700 miles). A 6.7 engine doesn’t filter any better, doesn’t hold any more oil, burns more fuel, plus it runs way hotter and dirtier internally, yet the manufacturer has increased the oil change interval recommendation. To us that doesn’t make sense and is evidenced by catastrophic engine failures we have seen in our shop.
Not sure what to think, the norm on these engines seems to be 10k miles

Cummins Diesel 6.7L Engine Oil Change Interval [Avoid Costly Repairs] - XL Mechanical Service Ltd.
The Cummins Diesel 6.7L is a great engine but there are things to really consider regarding oil change intervals. The important point to consider is that not all drivers are created equally. Do you just make short trips? Are you making consistently long hauls? Are you running conventional 15W/40...

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