Forum Discussion
T18skyguy
Jul 19, 2020Explorer
From what I've read, most of the CP4 failures are in rigs that are pushed to maximum horsepower, or get contaminated with water. That pump will explode if even a small amount of water gets in it. The pump has very fine tolerances, and it helps if you use 20% bio-diesel, or run an aftermarket lubrication like Optilube. I put a lift pump on my 2016 Duramax which helps the situation.
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