26th Oct 2004, 06:13

I own a 2002 Chevy 4x4 with a 6.0 vortex, when starting it up in the mornings the thing knocks, ask my Chevy dealer about it, he said GM said it normal, what a bunch of crap!!I have not been able to get them to even look at it, you would think GM as big has they are would stand behind the product they build, or at least give the owners a lifetime engine replacement if the motor blows up.

10th Dec 2004, 00:04

I also own a 2002 Chev 2500HD Crew Cab 4x4 with the 6.0L engine. I previously owned a similar 2001 Chev 1500HD Crew Cab 2x4 with the 6.0L. Engines in both trucks knock terribly at cold start-up. I've had two Chevy Dealers tell me the same thing on both trucks... its normal. My father has a 1999 with the 6.0L and it doesn't knock. One dealer says that Chevy is aware of the problem and it's a lifter on the #8 cylinder that looses prime, but it does not affect engine performance and cannot fix it. I love the truck, but embarrassed to start it cold. I think Chevy knows the fix, but too expensive to recall.

6th Nov 2005, 14:56

That knock that you guys hear isn't going to hurt anything, Its the small piston skirts that knock until its warm. I build chevy motors and I will only own a GM product and all of the 6.0's that I've owned has had that knock. Drive the truck normal and don't worry about it.

9th Nov 2005, 04:45

I just purchased a 2002 Chev. Silverado C1500 HD. It has 105K miles on it, but you'd never know that by the condition of the truck. The truck (inside / out) is in excellent condition.

It has the 6.0L engine in it, and at start up, there is no knocking of any kind.

Maybe I just got lucky... I hope so.

20th Jan 2006, 01:05

I also have this knocking problem on my 2000 chevy 2500 with the 6.0L. I am a GM Certified mechanic and I will tell you that this problem is normal for this engine along with a couple others including the 5.3L. GM will not do anything about it if a recall is what you are wishing for. Its not a safety item so forget it.

13th Feb 2006, 20:23

I own a chevy 2000 2500, bought it this summer. Unfortunately for me, I got suckered into it. See I bought the "like a knock" on a hot day. didn't hear a peep out of it, oh that's until the next morning, I go to start it, and the thing rapped hard. and I mean hard. I can't even hear myself think.. that is a hazard right there, Think of it a man driving a truck that knocks so hard that he might get in an accident because he can't even hear himself think, the truck is excellent other than the knock. No leaks or any other problems with it, just knocks. Junk! owell. run it Lilburn.

11th Apr 2006, 18:23

I own a 2002 2500HD Silverado with a 8.1, knocks a little on start up, but runs great after that. One problem is while driving it dies for no reason, but will restart on its own after 2 or 3 seconds. Dealer has no clue, can't fix until it dies for good. Other than that it's a great pick up.

22nd Apr 2007, 16:06

My 2003 doesn't knock in the mornings anymore, it only knocks all the time, as in constantly, between 1100 and 1400 RPM.

2nd Jun 2007, 20:59

Hi, I have 2004 chevy 2500hd 8.1 liter, using a quart of oil every 3000 miles, its now starting to knock at start up. it now has 38000 miles. i also have front suspension problem on drivers side. taking it in for warranty since it has extended warranty. ill keep you informed.

4th Jun 2007, 13:41

2001 Chev Silverado 2500 HD,6 litre Gas Engine, that has a hard start. I Have to try a couple of times before it will start. Does anyone know what this could be?

16th Jul 2007, 02:10

I just bought 2002 chevy X/cab 4 door 2500 HD W/6.0 liter.

I got the truck 2 1/2 months ago. It also sounds like a diesel when it is idling or when I mash the gas, and when the motor idles back down, the lifters start chattering again.

I also run a 1/2 quart of lucas oil stabilizer in my oil change just to help out the motor. I also don't like the sound of it, and I'm going to the dealer about. I may have to put new lifters in motor and send Chevy corp. the bill along with some legal backing? No wonder the guy sold the truck I bought. I know now he lied to me. It bothers me reading all of these bad reports about this motor.

31st Aug 2007, 13:29

I own a 2000 Silverado 6 litre engine and it knocks really bad at startup for about 2 blocks then goes away. I am also a real Chevy fan and sure think the Chevy people would take care of their customers better than this. I did go to Saddler Motors in Sault Michigan and was told that my engine was shot. They were to get back to me with all the problems and what it would cost to fix. But they did not even return my calls after I said I wanted to contact the head office to see why they don`t stand by their products. Michael Bronicheski.

4th Sep 2007, 18:56

I just purchased an 02 2500 Suburban. Knocks like an SOB only at lower RPM. At idle it kinda reminds me of a "mini me" 6.5 diesel. Right after I bought the truck I changed the oil (5w30) and put some Lucas in her. It got even louder. So I did another oil change, but first I tried the Penzoil engine flush treatment then I topped her off with 10w40 and some CD2 MAXX Detergent. The knock seems to have quieted down a bit, but is still noticeable. I know this "knock" is quite common for the Gm 6.0L. A friend of mine had a 04 with only 90,000kms and it knocked worse than my 02 does.

5th Sep 2007, 18:05

Has this knocking problem been corrected in new engines (2006-2008)? From what I have read it seems that most of the problems appear to be piston slap from the skirtting, has GM ever officially commented on this? Thanks.

12th Oct 2007, 23:53

Just bought 2001 chevy 2500hd with 220000 miles. it has a knock, but runs perfect. I was told the 6.0 is a 400000 mile engine if serviced properly. very nice truck, but just has that knock.

11th Nov 2007, 10:55

I have a 2002-Chevy 2500HD 4x4 with 6L (47,000miles).I do not hear engine noise, but I live in Florida. This truck is a gas HOG 12 mpg downhill with wind at my back. What gears does this pig have? My 1988 truck 5.7L (over all the same) got 14mpg with 1988 technology. What is the deal? Over all nice truck.

18th Dec 2007, 20:29

I had a 5.3 (not that its the same as a 6 ltr.), that was perfectly fine when I bought it. Then I changed oil, and found the oil to be purple (yes, I was wondering what plug I pulled). Well, I didn't have any purple oil, so I installed my favorite Valvoline, then, WOW, I notice a chatter now since the change. So I guess MY recommendation would to try some of that "Royal Purple" oil and see how that works. Hey... let me know how it goes (myonlyemailaddress@yahoo.com). Thanks!