Knock Or Tick When Cold

[outlaw1]

I have a 2001 1500 with a 4.8L Automatic. 100,000 miles. Bought truck new. no mods. Oil change evey 3-4k syn.

 

When I first start it When the weater is cold in the mourning I can hear a knocking or loud tick. Havent been able to locate the source. When the engine warms it is gone. On a warm mourning this dosent happen. Oil filter and oil has been changed several times. AC filter Mobil 1 10W30. Also this is the second winter I have heard this.

 

Any ideas.

[pwall]

Welcome to GM....most likely that is piston slap and is considered 'normal'.

[outlaw1]

Thanks for the reply. I have thought about the piston slap. But this motor was as quite as a church mouse up until last winter. Dont know how I would have reduced the piston to wall clearance.

 

Normal Huh. Who said that it is normal?

[pwall]

GM says it's normal.....of course they do. They would have to fix a lot of motors.

[chevy6490]

It is instability of the piston in the chamber, like pwall said, gm consideres this normal and no problems arise from it. Mine is terribly loud for a few minutes then its fine, havn't had any engine problems result from it.

 

Zach

[outlaw1]

I am not new to there normal knocks or noises. I was awareded this truck in 2002 on BBB claim on so called normal. I would advise you if you have low miles to make a claim.

[jhm]

I have a 2001 1500 with a 4.8L Automatic. 100,000 miles. Bought truck new. no mods. Oil change evey 3-4k syn.

 

When I first start it When the weater is cold in the mourning I can hear a knocking or loud tick. Havent been able to locate the source. When the engine warms it is gone. On a warm mourning this dosent happen. Oil filter and oil has been changed several times. AC filter Mobil 1 10W30. Also this is the second winter I have heard this.

 

Any ideas.

I have the same truck/engine/oil changed regularly. I only have 60k on it but last winter the cold start knock reared it's ugly head. Now I get it even in the fall if temps drop into the 40's. They claim it does no damage, I will decide for myself depending on what happens down the road. Once bitten....

[outlaw1]

I am really not satsified this is a piston slap problem. It clears up so fast on warm up. can't really tell. Almost sounds like a loud lifter.

[KB06YUKONXL]

I am posting on this thread because I have this on my 2006 Denali 6.0L . Took it to the dealer once at 24000 miles and got the "normal" response. Took it back at 32000 when the knocking lasted 3-5 minutes and still under warranty. The dealer decarboned the throttle body and removed the spark plugs and soaked the pistons with top end cleaner and the knock is gone. I requested an extended warranty and GM sent me a letter extending my 3/36000 warranty on the engine to 6years/100,000 miles. So I am thankful that GM has stood by their product. As for this dealer, they will get ALL my business in the future because they have treated me very well.

[minibike132]

You learn something new every day. The issue never makes it back to us. You all get the normal speech before it gets back to me. I have never really been satisfied with the "it doesn't cause any problems" theory but after 10 years I can't really prove it wrong. But I do have a real good customer that comes back and talks for a bit when he comes in and he's got the knock. I'm going to try a good top engine clean next time he's in and see what happens.

[truck1014]

Its the lifters!!! same on my truck its got 186,000 miles its done it for the past 30,000 miles normal!!!