Clean Exhaust Filter readout

An 08, purchased new in California without the DPF syetem...That sir, is about as unlikely as hens teeth.

The OP's "kid" is forty years old. He bought the truck new in California. It does not have, nor has it ever had, the DPF system.

O.P. needs to figure out what his kid really has and get back to us when he can get his story straight. Otherwise people are here wasting their time trying to offer help...

IMO the truck came from the factory with a DPF if your getting this message in the DIC. Whether its still on the truck or not is another question the OP needs to verify. Assuming the DPF is still on the truck then yes he just needs to drive it 20-30mi on the highway to get a good regen that will clean it out.

How long has he had the truck?

Could be Canadian? I know someone who bought a older duramax that the US government bought from Canada and it doesn't have a cat converter , etc

salem wrote:
My mistake, it's a 2008 (dang, time sure goes fast). That is prior to the DPF mandate.

All 2008 have dpf from the factory in the US. Many choose to remove it because of the problem messages and expensive repair bill they create. Also for the 2-4 mpg increase.

According to Chevy, from 2007.5 to 2010 they used the same LMM engine and DPF setup. But I could not find an online listing for the Duramax supplimental manual. You could call the local dealer and see how you can get one.

My mistake, it's a 2008 (dang, time sure goes fast). That is prior to the DPF mandate.

sh410 wrote:
If bought used, the previous owner may have removed it.

That would be a logical explanation. Unfortunately and probably unknown for the current owner of a low mileage truck, would also void warranty.

If bought used, the previous owner may have removed it.

It does not have the DPF system. He did not take it off, it did not come with one. I just mentioned that so you would know it didn't have anything to do with the DPF.