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Grit_dog's avatar
Grit_dog
Trailblazer
Jul 30, 2019

Time to kill the Cat

For anyone wondering, it appears that about 170k Miles is all you can get out of a Dodge Cummins Cat converter running a cheap, not so clean tune it’s whole life.
Been watching egts for a couple years now and after the same benchmark drive this summer, loaded heavy, same temps and grade, egts are a solid 200deg higher than a couple years ago.
Same trip, used to not be able to break 1200-1300 set in 5th gear up this grade. This year I could hit 1500 easy and 6th was renamed the smelter gear!
Anyone got a sawsall I can borrow?? Lol.

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  • RVingUSA's avatar
    RVingUSA
    Explorer
    Jul 30, 2019
    Grit dog wrote:
    For anyone wondering, it appears that about 170k Miles is all you can get out of a Dodge Cummins Cat converter running a cheap, not so clean tune it’s whole life.
    Been watching egts for a couple years now and after the same benchmark drive this summer, loaded heavy, same temps and grade, egts are a solid 200deg higher than a couple years ago.
    Same trip, used to not be able to break 1200-1300 set in 5th gear up this grade. This year I could hit 1500 easy and 6th was renamed the smelter gear!
    Anyone got a sawsall I can borrow?? Lol.

    Hi
    It would be better to knock the guts out of the cat and just weld it back in. Then you will never have to deal with the problem again. If you get the visual inspection the exhaust NAZI’s you want get a ticket for modifying the exhaust.
    CH

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