warm start knock

[03konxl]

New here but been a guest for a while.My 5.3 knocks on cold and warm starts.Most noticeable after sitting for an hour or so.Hell it will even knock after sitting 10 minutes but just for a few seconds.It lasts for about 30 seconds.When cold it takes a minute before it starts knocking,goes away then returns a couple minutes later but not as loud.It continues until close to op.temp is reached.115000 miles- mobile 1 with delco filter.

 

[Donnie Yukonie]

That is because all the Oil is settled into the Crank case and it takes a second for the Oil pump to pump it back over the top, No harm in this as it will lubricate the parts before any heat or damage could occur

 

[03konxl]

Thanks for that imput.Glad to hear its not a big deal.It is bearable anyway, not very loud.And it runs like a champ.Nice rig by the way!!!

 

[Donnie Yukonie]

Thank you , No problem

 

[jdpber]

its annoying but a common thing.. i like to think YAY its diesel as it warms up.. lol

 

[03konxl]

ya.but i love the power and comfortable ride.Sick ass Tahoe.Looks like fun for some desert trails.

 

[JasonFH]

I get the same thing on my 05 5.3 with 117000 miles on it and was told to get an oil filter with a back flow preventer... Next oil change is coming up and I will let you know if that does anything. Definitely drives me nuts because it isn't a noise that I had until just over 112k.

Sent from my SPH-L710 using Tapatalk 2

 

[Yukonboy2014]

...i like to think YAY its diesel as it warms up.. lol

^^^^ Every morning haha

There is no real damage being done. As these motors grow older, they wear out. It is just the oil that has been settled down into the pan, hasn't reached the top of the block yet. No harm, nothing to worry bout.

 

[M Hankel]

Its piston slap. When cold the piston is smaller than it is once warmed up. The added room in the cylinder is the piston rocking in the cylinder during the transition at the tops and bottoms of the cylinder. This was a common complaint from new owners from 1999-2003 and GM even had to replace some engines under warranty for excessive noise. GM remedied the problem in 2004 I believe when they added an anti-friction coating to the piston skirts.

Probably more info than you wanted lol...

Mike

 

[pwtr02ss]

They also added piston oilers