Originally Posted By: dnewton3
And the Cummins targeted lifecycle is B50 @ 300 (50% bearing life estimated at 300k miles) IIRC. So, with 15k mile OCIs, Cummins expects their engines to have decent remaining bearing life at 300k miles. Many of todays gasser engines have either dumb OLMs at 7.5+k miles or IOLMs that show 10+k miles are doable. Many of those vehicle OLMs are predicated on simple conventional lubes.
My understandig of a B rating is different. Take for example my C7500 below. It has a 7.8l Duramax/Isuszu 6h engine which carries a B10/400 which means, according to Isuzu, 10% of the engine population will require a major overhaul before 400,000 miles.
So I would take the Cummins B50/300 to mean 50% of the populaiton of those engines will require a major overhaul before 300,000 miles.
And the Cummins targeted lifecycle is B50 @ 300 (50% bearing life estimated at 300k miles) IIRC. So, with 15k mile OCIs, Cummins expects their engines to have decent remaining bearing life at 300k miles. Many of todays gasser engines have either dumb OLMs at 7.5+k miles or IOLMs that show 10+k miles are doable. Many of those vehicle OLMs are predicated on simple conventional lubes.
My understandig of a B rating is different. Take for example my C7500 below. It has a 7.8l Duramax/Isuszu 6h engine which carries a B10/400 which means, according to Isuzu, 10% of the engine population will require a major overhaul before 400,000 miles.
So I would take the Cummins B50/300 to mean 50% of the populaiton of those engines will require a major overhaul before 300,000 miles.
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