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Author Topic: Reflashing ECM on 2004 ISL 350  (Read 323 times)


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Reflashing ECM on 2004 ISL 350
« on: October 07, 2017, 03:48:33 PM »
Hi there, I was doing some searches but coudn't seem to find what I was looking for in a recent discussion. I have a 2004 Itasca Cummins ISL 350, CAPS. I want some more information on reflashing to get more HP. I pull a 4500lb boat up and down a lot of hills here in Oregon.

There are a lot of programmers out there with a big variance in price. Thought I'd check in here as a first step.  Thank you.
2004 Itasca Horizon 40KD 350 Cummins, 60,000 miles

Gary RV_Wizard

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Re: Reflashing ECM on 2004 ISL 350
« Reply #1 on: October 08, 2017, 11:13:43 AM »
I don't believe there was an ISL 350, at least not in the motorhome application. The ISL is an 8.9L engine and I believe it has a minimum rating of 370 hp in 2004, with 400 hp more common.  The 350 hp engine for motorhomes is the ISC, an 8.3L diesel. Winnebago lists either a Cat C7 7.2L 330 or Cummins ISC 350 for the 2004 Horizon, but I think I've heard that some had an ISL 400 as well.  See brochure at https://winnebagoind.com/resources/brochure/2004/04-Horizon-bro.pdf

There are lesser Hp versions of the ISL, producing lower torque and used in other applications, e.g. fire trucks. Perhaps your engine was replaced at some point with one of those?  If so, ignore my remarks above.  I'm just trying to avoid the mistake by buying something for the wrong engine.
Gary Brinck
Summers: Black Mountain, NC
Home: Ocala National Forest, FL