Inquiring engine minds

[Bluebird]

Dumb question, great replies I hope. Why does the Cummins 5.9 continue service for hundreds of thousands of miles? Please give as many details as possible. Thank you all who contribute to my amazed mind. Many folks appear to have new, modern vehicles, even my wife. I am content with my truck. Blessings to all, Patrick

 

[EDankievitch]

It was just built right. Sometimes even a blind squirrel can find a nut. No really they built it on tried and true hard work and testing. And they didn’t cheap out. Cummins just builds engines nothing else. If they don’t work they out of business.

 

[BigPapa]

One reason they last like they do in our trucks is that they were dramatically de-tuned from the power levels they were designed for, especially the early 12 valve engines. One of the things the ”B” 5.9 was designed for was continuous duty in marine applications at well over double the power rating in our trucks. For instance, for years one of the favorite power increases in our trucks was to install the injectors from a marine 370HP application. The most they ever rated the 12 valve in the Dodge trucks for was 215HP. The 1st Gens and the early 2nd Gen autos were rated at 160HP.

 

[petersonj]

Also, the in-line six cylinder long stroke configuration is a proven concept that delivers high torque at low rpm's naturally. Combined that with one journal bearing per piston / rod assembly and abundance of main bearings - one can't go wrong with reliability and longevity. And then it is topped off with a turbocharger that has its exhaust turbine located close to the cylinders for maximum efficiency.

- John

 

[Wayne M.]

I agree with all the above. Add on that Cummins runs a tight ship in quality control- maybe more so at that time. Also, especially with the newer engines, trouble is seen when the wick is turned up without the proper tuning.
The 12 valve trucks were such a bulletproof product.

 

[Bluebird]

Outstanding info folks... y'all made my CTD day. I'll keep firing 'er-up, everyday!
Blessings, dont let them sneeze on you
Patrick

 

[sdeeter19555]

Plus, keep in mind the RPM they turn, about half to 1/3 of a gasoline V8...less turns is less wear.

 

[EDankievitch]

Less RPM but way more load on the bearings. Can’t get something for nothing. That is why the bottom end was way overbuilt.