Injector knock??

[dmax515]

I just bought my first diesel and am very happy at this point in time. Just a couple of questions since I do not have another Duramax with which to compare this to. My truck is relatively quiet at idle, no smoke at any rpm level and I'm getting around 18-20mpg average empty around 12-13 towing a 5100lb trailer. Not sure what the truck should sound like, but I keep reading how it should be real quiet but if riding by a road partition where the engine can be heard quite clear, It sounds a little noisy around the 1600-2400 rpm range when driving only. Once you accelerate it quiets up substantially and just flat out pulls and you hear the whistle. Should I be looking out for anything? I keep reading about injector knock and want to assure myself that I'm just making something out of nothing. No symptoms at all, just not sure of what it should sound like off of idle just cruising. I've driven a 2001 Ford Powerstroke and although noisier than mine, the sound I hear from the ford is at a much quicker frequency whereas the noise I hear in the cab of my Duramax is a slower frequency almost sounds like a continous rod knock in a gas motor or loud pinging at a slower frequency? Just not sure what the Duramax should sound like at speed? The truck is a GM Certified that I just bought 3 weeks ago with 47K miles on it. I have 3 months of full warranty left on the truck plus the 100K Engine warranty. I want to be sure I'm not having any issues as the tech at the dealer says the truck sounds just fine.

Thanks for any info to help with my paranoia..

[ 05-14-2004, 04:51 AM: Message edited by: dmax515 ]

[oyazi]

Dr. Phil ?
:D ;) smile.gif