i found this on the chevron web page :eek:

The new api CJ-4 performance category was developed to address both the unique needs of new engines and to protect older engines while enhancing the life of emission control systems as required for regulatory compliance in order to meer new emmission standards for new heavy-duty engines starting January 2007 engines will be equiped with advanced emission control technonogies including diesel particulate filters (DPF) and in most cases exhaust gas recirculation API CJ-4 was desighen to ensure that the dpf cleaning did not occour before the 150,000 mile mark as mandated by the EPA and to improve oxidation to combat the increased egr rates over the 2002 engines
check it out yourself and you tell me am i reading this incorrectly?
http://www.delobike.com/Chev%20CJ4%20Q_A.pdf
if that link is not working



this one will Delo CJ4 FAQ (http://www.delobike.com/Chev%20CJ4%20Q_A.pdf)'s
Frequently Asked Questions its a tab on the right side of the page
http://www.chevrondelo.com/en/deloworldwide/uscanadamexico/default.asp



THEN WHY DO I RE-GEN ONCE A WEEK????

Uneducated guess.. but I think that means the real cleaning of the system. When you have to get in there and get all that toxic ash out. Not the incremental that happens every other tank or so.

That info applies more for the heavy duty diesel market. I have already seen the cleaning equipment and yes they are hoping for 150-200 but i dont see this happening in the regional market. these trucks dont get the egt,s high enough to burn it out.

Real cleaning??? Mine will be gone then. I swore to myself I would at least keep it till the 3/36 is up...maybe the 100k powertrain mark.........probably not.

To each their own. I will hopefully keep my truck a long while. Not because I need to, but because I'd like to. I'm sure we'll see if my position sways by then. But, I'm not a huge fan of having to PAY to get these things cleaned out. I'll most likely cut it off after the warranty is done. Then the problem will be solved for me.

The link is correct. There is a ton of information on DPF technology in these forums - it just requires some searching. However, to answer the specific question, during regeneration cycles the DPF gradually accumulates ash (combustion by products) which eventually plugs the filter enough that it has to be cleaned. This is a completely separate phenomenon to the accumulation of soot (carbon) between regens.

There will be a whole new industry spring up around this requirement because you can bet that GM dealers will want an arm and a leg to do it for you. Blowing out the ash with compressed air seems to be a common method but it is not a "do it at home" process.

This is not going to be something we can avoid. Prior to the EPA mandated life GM will have to pay if your DPF clogs up with ash, but after that it will be your cost. The truck won't run with a clogged DPF.