Light duty vs Medium duty

[Big_Daddy_T]

Its the old discussion but I have new info.



I have been looking for years for a chance to run down a t444e to read the emissions tag. I havent found one. One of the very nice guys over at the diesel stop looked for me. The t444e is rated as light duty by the epa.



I found this very interesting. It puts to bed a lot of old arguments. Remember the duty rating in this case is strictly for emissions. GaryK7GLD wrote an email to cummins some years back and posted the epas guidelines for duty ratings.

Thanks for your email request about emission duty cycles.



There are 3 levels of EPA certifications:

Light-heavy duty, Medium-heavy duty and Heavy-heavy duty.



Light-heavy duty engines... ... ... ... expected emissions warranty life 110,000 to 120,000 miles

non rebuildable engines limited gross weight capability



Medium-heavy duty engines... ... . expected emissions warranty life 185,000 miles

rebuildable engines for vehicles up to 33,000 pounds



Heavy-heavy duty engines... ... ... expected emissions warranty life to exceed 500,000 miles

rebuildable engines for heavy duty use for vehicles up to

120,000 pounds



Cummins only sells Medium-heavy duty or Heavy-heavy duty engines for vehicles in excess of 8600 GVWR.

The engine life-to-overhaul expectations for the Cummins B5. 9 series 12 valve mechanical engine is 300,000 miles and 400,000 for the ISB 24 valve electronic engines.

The C8. 3 and L10 engines have expected life-to-overhaul or 800,000 miles.

The M11 engines have 900,000 miles and the N14 has one million mile expected

life-to-overhaul.

It was a fun thread. Heres the link. https://www.turbodieselregister.com...pp=15&highlight=medium+duty+light+powerstroke

 

[rbattelle]

I read the thread to which you're referring over at the Dieselstop. I thought your information was very good. Here's the thread over at TDS. It's pretty good, and Big Daddy gives a good explanation of how the duty rating is determined.



-Ryan

 

[Big_Daddy_T]

Actually I have to give the credit to GaryK7GLD.

 

[rbattelle]

Is there anything Gary doesn't know? Methinks not...

 

[JPope]

"Is there anything Gary doesn't know? Methinks not"



Subtlety