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Old 01-03-2020, 10:02 AM   #2 (permalink)
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Join Date: Jul 2013
Location: N.E. Oklahoma
Posts: 14,781

Originally Posted by VipeRTBlck View Post
red the stuff online and seen places trying to make a lawsuit over the cp4 failures on these lml's. my question is, how much should I worry over this? from briefly reading, the pumps are designed for European fuel which has more lubrication properties than US fuel. i'lll frequently add powerservice to my tank as it has a lubricator (use to add 2 stroke oil in my lb7 but can't do that on my lml as I still have the emissions intact in my exhaust). aside from that the truck is 100% bone stock for warranty reasons. I bought an aftermarket (non-gm) extended warranty from a company called AUL that was offered and supplied by the dealer at time of purchase on the truck. I've read horror stories of the prices it costs when the pump fails. truck's a '16 with 20k on it. runs and drives fine. first fuel filter change was at 7700 miles and the second ones due now at 20k. no, the DIC isn't saying it's due; I just do it every 2 years regardless.

with the stuff I've read i'm contemplating selling the truck and avoiding any trouble financially....is it really that big of an issues with these?
Using fuel additive can help.
Also, adding a lift pump to stabilize fuel pressure and eliminate the possibility of fuel cavitation to the cp4 will help as well.
The stock Duramax does not have a lift pump and relies on the cp4 to pull fuel.
The lift pump ensures a constant feed for the pump and helps lessen the chance of failure.

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