Knock at start...

sleblanc63 · January 9, 2015

Maybe I hadn't noticed it before and it's been happening... but walking out of the office today I remote started my truck and heard a pretty good knock at ignition. After lunch walking back to the truck I did it/ heard it again.

Anyone else?

redwngr · January 9, 2015

All I notice is an exhaust rumble...

sleblanc63 · January 9, 2015

All I notice is an exhaust rumble...

#6.2exhaustrumblebragger lol

POS VETT · January 9, 2015

Yep. Every time.

SMiller · January 9, 2015

All I notice is an exhaust rumble...

But the new 6.2 has wussie exhaust note, I miss the old 6.2 exhaust!

f8l vnm · January 9, 2015

i think the loosy doosy noise is the Direct Injection ...its for sure sloppy

TJay74 · January 9, 2015

I hear it every time as well at start up, it is more pronounced if you remote start it since you are out of the truck to hear it.

soltys · January 10, 2015

I find the colder the temperature, the more it "knocks". But seeing as you're from Texas, you can probably through that idea out.

HondaHawkGT · January 10, 2015

Could this be what you're hearing?

"At temperatures of 32°F (0°C) or colder, when the engine has been sitting for a few hours, it is possible to have air enter the pump through normal oil drainback. Upon start-up, a short rasp sound may be heard from the front of the engine. It is most often heard during a remote start. This is a normal condition."

http://sandyblogs.com/techlink/?p=3134

MudMutt · January 10, 2015

I never heard a knock at startup but since it started getting cold around here I do hear the rasp from the front of the engine. Once it is running though it's super quiet.

TJay74 · January 10, 2015

That is probably it, it is more of a rasp but from a distance it sure does sound like a BBBRRRAAAPPP for just a second or so.

BillsLT · January 10, 2015

I too hear it with my DC and with my previous RC more of a BRRRRAAAAAPPPP sound also.

Told my wife when she said what the hell was that "Thats my my "G"iesel start up sound lol

glcbn · January 10, 2015

Even with that little hiccup on cold starts, these new ones are super quiet compared to the old 5.7 Vortec. You'd swear those trucks had diesels, and the colder, the louder it rapped and the longer it rapped. Then like magic, it's quiet. Kind of funny. My '98 Silverado did that on cold startups for all of its 285,000 miles.

thepewterpooter · January 10, 2015

I work at a chevy dealer and talked to a mechanic as my 02 sierra does that too. All the mechanics agreed it is nothing to worry about as some tend to do that. I don't know about the new trucks but mine has very high miles on it now and has ran fine its entire life.