(08-08-2021 )KW660_16 Wrote: [ -> ]I don't even know if I want to drive in CA anymore bc fuel is $6/gal and lots of rules. But who knows. Ok so the general consensus is 871 best. 22xx fine as long as you fix fuel filter every 400k?
2250's and 2350's are fine as long as you keep after the fuel pump every 400k miles...
That sounds about right, and is the experience of most of the people who own them on here.
A friend of mine that is the GM at a mid sized fleet that runs nothing but KW's with Cummins just showed me maintenance records on for a cm2250 that has 1.2 million miles on it. They pulled it from the OTR fleet and now use it as a local runner. But it has never had any major internal engine work except a couple injectors and the normal little stuff you have to deal with in that milage time frame. I was quite impressed. They are the typical fleet that goes off of Cummins recommended 40,000 mile oil changes. So it's definitely possible to get a long life out of the newer Cummins. They have a few cm2350's and x15's that are pushing high mileage too. Not a million but up there. They generally don't keep them that long because drivers won't drive them that old.
It depends on how the engine is used and what its HP ratings are. If you use more fuel with more engine pressures more piston ring seepage will occur and the oil will get contaminated sooner. I change my oil every 25K miles (thinking about shortening it) and I can tell diesel is in it and its thinner when I drain it. You really need to do oil analysis if you are going to extend oil changes so that you know EXACTLY what that oil is doing to your engine.
Another thing. Oil is cheap. Why take a risk and split hairs over when you change oil when an engine rebuild costs $30-40+ thousand dollars. over the life of 1 Million miles OR 10 years you save about $10,000 on oil. BUT you increase your risk of long term expensive damage on your engine significantly when your oil is not in ship shape. Why gamble $40,000 just to save $10,000. The math doesn't add up.
I saw a post on here somewhere about buying a used truck that was already de-mandated. What is everyone thoughts on that? I am in the market for a decent used truck with a cummins.
also what are everyones thoughts on the cm570 or 571(I forget which one it is?) basically the 2002 cummins six 15? I heard about signature 600 being bad. Is this one better?