Yes, Some 12 valve Cummins came with cat converters.
I do not know the last year but they started in 94 and ran through about 97.
Depending upon your states tests, the cat is required.
While I lived in Nevada, the cat was inspected during the smog tests.
Now that Im Missouri, the vehicle inspection still requires a cat.


Rich

 

My first diesel, a 96 2wd had a cat. My 98.5 was straight piped before I got it.

 

i guess i'm not the only one with a '96 that used to have a cat.

 

My early 94 (Its truly an early 94, has the odd trackbar and the odd bed.) had a cat, there is even a plate on the motor that says so. Its also not a cali truck.


Travis

 

Production 1/1-94 started Cats, ended when the 24V came out. I can't find my source to back that up so far, but mine still has her kitty.......

 

My truck has a NON-CATALYST sticker right above the radiator, and every truck I've looked at around here has had the same. I've looked at 95-98 trucks with auto's and manual's.

 

ALL 12 valve trucks sold in the US came with cats except early '94
With the introduction of the 24 valve in '98.5 the cat was replaced with a resonator.
Engine evolution here http://dodgeram.org/tech/dsl/Facts/epa_changes.htm

 

So according to that website the EARLY 1994s without a CAT didn't have the p-pump either? I thought all 2nd gen 12vs did. Am I reading something wrong?

 

I thank i found the offical deal on this subject. I couldnt find out how to link it to this page. But this is what i copyed.

1994 models built from July 1993 to January 1, 1994 DO NOT have catalytic converters.

Improvements to meet Jan 1, 1994 EPA standards

SO I HOPE THIS HELPS SOMEONE SOMEWHERE! : )

 

My "95" had one

 

whats the diff between a cat and a resinator???

 

I believe the cat has screens in it like a beehive to filter soot and burn Nox. The resonator is free flowing used to reduce vibration and some sound.

 

Does anybody know if the cats have a similar outer shape and design like the resonators from the 24 valve trucks?

 

Pretty much identical.

 

Cats are bullet shaped, resonators have flat ends just like a muffler. So no they're not at all shaped the same way.

Infidel is correct; all 12 valves from January 1994 til the last 98 12v had cats, it did not matter if it was a cali truck or not.
I don't know what Kas83 and that part of Wisconson have going on as I have never seen non-cat stickers ever installed from the factory, but I have worked on trucks from all over the country, and they all originally had cats.

Emissions testing is different everywhere, many areas don't test at all.
Here in Washington, the urban ares only do a tailpipe test as you romp the throttle, there is no visual component inspection. But the outlying areas don't test, even though those people commute to the city. Lame!
I know in Colorado they do visual inspections.