Cummins ISX15 Liner defect causes high oil consumption

Attached are details of defective liners leading to high oil consumption. Cummins usually addressed out of warranty issues using "Policy" dollars. If outside base warranty then easy to get "Policy" help at 75 percent up to 4 years and 400,000 miles or 50%-25% at up to 500,000 miles.

 

"DieselTech_Aus" - You are describing a completely different failure mode due to the poorly designed cylinder kit and insufficient cooling near the top of the cylinder.

The defect described in the attached TSB is do to a manufacturing defect of the liners themselves. The liners are made in China by a Wisconsin supplier named Menominee. The liners are then shipped to Menominee in WI and machined. The problem is the were using a 3 stone hone on the liners which left a lobing pattern of high and low spots that would then cause oil consumption. This oil consumption woul happen early life and be noticeable before 50K miles of delivery of truck. The supplier ran into supply issues keeping up with demand and perhaps used a cheaper hone or sped up the process which caused the issue. The curious thing is, when they fell behind, they asked their Chinese supplier to help out be doing some honing in China. The Chinese used a 6 stone hone and suffered NO lobing issues. Anyway when the liners were supplied to Cummins there was no distinguishing which liners we WI Vs China honed. You could have had an engine with liners from both in one engine. Cummins has no quality control process for determining which supplier honing process was used so its possible to have two engines built in a row with all Chinese, all Wisconsin or a mixture during this time.

So, if you have early life high oil consumption it is NOT carbon packing. It is probably liner lobing and should have the liners replaced. You also want them to replace the pistons to the new "APR" (Anti-Polishing Ring" style piston liner to avoid future Carbon packing issues.

in a nutshell, I wouldn't touch a 2010-2013 built ISX15 engine with high oil consumption unless the APR cylinder kit was installed and the DPF was replaced with new or a factory Recon. Also these engines suffered terrible fuel pump failure rates due to ceramic plunger failures in the fuel pump due to debris in the oil due to a poorly designed oil bypass valve that would stick open and allow unfiltered oil through. Also the Camshafts were prone to damage from having too much of a crown on the rollers leading to high stress there and poor roller bearing materials that would degrade and oxidize causing them the hang or stutter thus causing the oil film to be scraped off the camshaft and scratching it. Once scratched, the cam would eventually beat on that scratch until it flat spotted.

Combine all this with the big 1000+ truck fleets pushing longer and longer oil intervals and its was a recipe for disaster.