2009 5500 Duramax idle question

[JustinD]

I have an 09 5500 with an LMM, it idles for 10 mins or so and then automatically shuts off, can I change that with EFI? Also can I just flash it to a stock LMM 2500HD file? Would like a little more power but don't want to hurt it. Hopefully I can disable the idle shutoff with my EFI????

[JustinD]

I read the truck, it uses the same 8594 OS as some of the other 07+ trucks I've seen. It has a PTO output, and an exhaust brake, so just a reflash to a 2500HD OS wouldn't include those things right? Thanks for any input.

[Brian1]

I am not sure on the tuning of the medium duty trucks but it can be done. You mean you start the truck with the key and if left to idle for 10 minutes it shutsoff on its own with the key still in and on?

Brian

[JustinD]

Yes, it has a feature where if you let it idle without the PTO engaged or without your foot on the brake pedal it will shut itself off.

[killerbee]

That is odd. At first it sounded like a remote start safety feature.

Does it have a factory dpf?

[JustinD]

Yes it has a DPF, he wanted to delete it with a delete pipe but I think I talked him out of it for now, I'd still like to disable that idle feature though, I was also thnking that I could flash it to a stock LMM 2500HD file, would that be ok? I figured he'd have a little more power but not goning to kill it??? What do you think?

[killerbee]

I am just making a guess here, as I have scant knowledge of newer MD features. Are there any codes? Is it possible that it is happening because a regen is not progressing on schedule? Regen will not proceed effectively at idle, not enough EGT can be produced

[JustinD]

Hmmm, no codes. I did read about someone disabling it with a Tech II on his truck though, it has a button on the dash that forces a regen too, it works. Truck has 17k on it basically like new.

[killerbee]

It would be interesting to see if it changes with a LD file.

[JustinD]

I may just have to try it, worse case I can just put it back.