Recalls & Engine Knock Info

[Chevy Princess]

SafetyAlerts
August 23, 2002
General Motors Has Recalled nearly
525,254 vehicles
(SafetyAlerts) - General Motors Corporation Has Recalled the 2000 Chevrolet Suburban, Chevrolet Tahoe, Chevrolet Tahoe, Chevrolet Silverado, GMC Yukon/Yukon XL, GMC Sierra because of airbag problems.

Number Involved: 525,254

Dates of Manufacture: February 1999 – February 2000

Defect: Some pickup trucks and sport utility vehicles have an air bag sensing diagnostic module (SDM) that contains an anomaly that could result in the driver and passenger’s air bag failing to deploy during certain frontal crashes. In a vehicle crash, front seat occupants may receive more severe injuries.

Remedy: Dealers will recalibrate the SDM in the affected vehicles. The manufacturer has reported that owner notification is expected to begin during late August 2002. Owners who do not receive the free remedy within a reasonable time should contact Chevrolet at 1-800-222-1020 or GMC at 1-800-462-8782. [NHTSA Recall No. 02V178/GM Recall No. 02029].

Important Note Regarding Auto Recalls
Frequently SafetyAlerts will list auto recalls before
your dealer will know about them. If you have a vehicle
affected by one of these posted recalls be sure and
write down the NHTSA CAMPAIGN ID Number.
If your dealer doesn't know about the recall when you
check, ask them how they are notified of recalls and
when the next update is due.

http://www.safetyalerts.com/recall/a/02/v00312.htm

[Chevy Princess]

GM Has Recalled the 2003 YUKON XL, SUBURBAN and AVALANCHE:
Component: FUEL SYSTEM, GASOLINE:STORAGE:TANK ASSEMBLY
http://www.safetyalerts.com/recall/a/02/v00586.htm


Make : CADILLAC Model : ESCALADE Year : 2003
Make : CHEVROLET Model : SUBURBAN Year : 2003
Make : CHEVROLET Model : TAHOE Year : 2003
Make : GMC Model : YUKON Year : 2003
Make : GMC Model : YUKON XL Year : 2003
Component: STRUCTURE:BODY: DOOR:HINGE AND ATTACHMENTS
http://www.safetyalerts.com/recall/a/02/v00570.htm

[Chuggs]

I just read this and thought some of you may be interested in reading it as well:

From Pages 90-91 of the March/April '03 issue of TruckTrend

We've finally gotten an answer on the cold-start piston knock involving 4.8, 5.3 and 6.0-liter V8's in '99 to '02 GM cars and trucks. General Motors has previously released a Technical Service Bulletin explaining the condition that occurs after approximately 12,000 miles and a normal accumulation of carbon above the top piston ring.

I spoke with Sam Winegarden, GM program manager and chief engineer for small- and big-block engines. Sam explains that following extensive testing, General Motors is confident the start-up noise will have no adverse effect on performance or durability of the engines involved.

As opposed to the larger pistons of earlier design engines, today's technical refinement requires the use of smaller pistons to reduce weight and reciprocating mass in order to aid in efficiency and durability. This reduction in size also reduces the stability of the piston in the cylinder bore, which can promote piston noise.

Preliminary testing on these engines showed no sign of a problem, but, as in many other situations, the symptoms came to the surface after the vehicles were subject to normal driving conditions.

The manufacturer's stand on the issue is that it doesn't warrant a service bulletin or recall promoting a repair. We were also assured the problem has been corrected on the '03-model line with a piston-design modification along with the addition of a polymer coating.

My response was from the viewpoint of a consumer who purchased a brand-new vehicle that developed a notable engine knock before the first major service. The complaint was not only about the annoyance of the condition, but also the effect on resale and depreciation.

The answer was that General Motors would be dealing with the consumer on a case-by-case basis, and complaints have been resolved by means of warranty extension and parts replacement.

The owners of involved vehicles exhibiting the cold-start piston knock should have the service manager of the GM dealership, which has been evaluating the noise, contact the manufacturer's zone representative. Hopefully you can come to satisfactory terms.

[treyZ28]

wahoo, go 03

[treyZ28]

ive been told by inside sources that the cheap piston MFG is at fault-
but WTF do i know
I'm calling big skrew up on someones end that isn't that big of a deal- it just seems really really bad.
this is to save face and money

[ricjr76]

hey guys i'm new here but let me give you a little info. i have a 2001 sierra with the 5.3 and developed a "knock" and the dealer tried to tell me they never had any problems with this particular motor and that what i was hereing was cheap gas or carbon build up. i asked if he could keep it over nite and get a cold start in the morning, he agreed. the next morning he called to inform me that the connector rod had broke when they started it and punctured my block.-------------new motor -------------------ha ha ha.they dropped in a complete motor assembly,so much for carbon build up. well the new motor is 8 months old and developed a "knock" also. back to the dealership. they have it all week and say no noticeable noise, i say bull**** and they send me on my way. i have to get on the phone know with custermer service i'll keep you posted on what they say. i hope everyone gets what i'm trying to say--------------don't believe its just carbon because with out the skirts on the pistons and how they build these motors loose for more ponies you cause excessive play that DOES put more stess on the connecter rods as well as uneven wear and tear on cylinder walls and pistons,,everything bassically. just like racing..build it loose...rebuild it more often

[021500HD]

Personally, I think that GM is full of it and trying to see if they can pass this off until these engines are out of warranty. I am sending this thread to my machinist.

[Steveman09]

Hey guys suggestion.....


Why dont you go pickup some Combustion Chamber cleaner and clean out your pistons and everything???

It only cost like 20 bucks at the most and if the problem goes away it was carbon buildup, if not you have motor problems?!?!?


This is a simply tool that I use all the time and has fixed some knocks that were just carbon buildup. Jeep V8's had this similar problem with excessive carbon buildup.

[cyanideg33]

My 99 yukon denali has the same cold start knock. it has 99K on it and I thought it was just going bad!!! What a relief. It does go away after like 30 seconds after I drive it.

[Dan]

CSK.....TSB's

http://www.pistonslap.com/tsb.htm

[SUBMAN]

Wifeys boss just bought 2003 XL and had no idea about recalls on fuel and doors. He has had a major prob. with the a/c. Any recall on the enviro controls?
Thanks fo rthe info
Subman

[gmcsid]

Originally posted by TireFryer30th
I am also having problems with my A/C...it takes a long time for it to get cold, and sometimes it barely gets cold.

TireFryer

I have seen a lot of cycling switches malfunction. It's located on the accumulator, (long cylinder at passenger side firewall). When the a/c is blowing warm, see if the compressor clutch is engaged. If not, tap on and wiggle the connector of the switch and see if the clutch engages.

There is also a bulletin (#02-01-38-007) It explains some additional a/c performance checks for the tech to do for a poor a/c performance complaint.

SUBMAN, there are no a/c recalls for the 03 XL. There is a bulletin for poor a/c performance at idle or in traffic. (#01-01-39-004A ) The fix is to install an auxiliary electric fan.


If anyone want's to check your vehicle for recalls you can post or PM me your VIN and I can check for open recalls and warranty history.

[Elwood]

LIke the rest of the English Speaking World, I too have been to my dealer about the problem. GM has a service bullitin that states that engine knock at start up for 90 seconds is considered "normal" and no adjustment or correction is necessary.

After that, my dealer would not touch it.

The good news is, I know a guy who works the snot out of his 5.3 and he has 225k on his truck. It knocks like dice in a beer can when he starts it, but it runs strong and uses no oil.

[aklim]

That sucks. I just bought a 2001 Silverado 1500 with the 5.3 Vortech. Guess that means I am SOL right? Since I am not the original buyer and it has 70000 on the clock when I bought it?

[pflug24]

just out of curiousity what octane fuel and weight oil is everyone using that has the knock in their engines?

[bakerboy90660]

Does anybody know if this was corrected in the 03 line?

[Marine]

I *****ed to GM directly......... got a 6 year / 100,00 mile extension on the motor.

Jeff

[Flipper]

Gentlemen,
I am new here so please dont rip my head off on my FIRST post! I am not sure I want to admit this based on this message thread, however I am a Service Manager at a UN-NAMED Chevrolet Dealership.
I have read the posts on this thread and may be able to offer some advice, confirmations and clarity!

1. I have not seen or heard of 1 single engine failure DUE to the piston problem. I did notice a post by someone about a connecting rod failure--- DIFFERENT SITUATION --! DIFFERENT SOUNDING NOISE! I can see with all the publicity of this concern how it might be confused.

2. There is also a GM TSB for a "torn" O-ring at the oil pump pickup causing aeration of the oil, the difference in the two would be that this was an assembly problem and should have been noticed from day one.

3. The good news is the noise is caused by carbon build-up on the pistons which can be "De-carbonized" and the noise will go away! The bad news is, it's like that bird that you set free, it comes back! cause it is meant to be. Again the good news is, it is just annoying!

How do you affectively de-carbonize?
During the warranty period MOST dealers will do it for you free under warranty.
If you are out of warranty the best and most effective method is:

1. Remove your spark plugs.
2. If you do not live in california, go to your local dealer and purchase "top engine clean"
3. Pour it into each cylinder.
4. LET IT SIT OVERNIGHT!
5. The next day, turn the engine over 180 degrees and pour more "Top engine clean" into each cylinder.
6. LET IT SIT OVERNIGHT!
7. Next day re-install your spark plugs.
8. Start your engine, IT WILL SMOKE AND SMELL BAD!
9. Once it stops smoking, Shut it off and CHANGE THE OIL!!
Make sure you change the oil!!! While it was sitting the Top Engine Clean was going past your rings into your crankcase!!

I like you guys own one (actually two), and I am just as unhappy with the situation as you are!

Just a little note there was for a short time, a GM TSB Listing part #'s of updated pistons for the 6.0's as they by far have the problem the worst. The part # was for the same pistons now used on the 2003.

I personally have replaced the pistons on my 6.0 and used Diamond forged pistons, and have not experienced any problems!

Sorry this is so long and I hope it helps!

[PeteChevySales]

Piston-slap happens on NEW 5.3 V-8's. As I am frequently the first salesperson at the dealership in the early morn I move a blocker (generally an Avalanche or Silverado or Suburban) out of the way for the day's traffic. If it's even slightly cool (that's low 70's for us so-cal folk) I've heard the snap-snap-snap of slap at start-up.
I wouldn't call it a Problem so much as an Annoyance, but then again I don't own one. The little 3.1 V-6 in the Buick Century does the same thing. Call it a quirk or call it poor engineering. Even if it doesn't actually cause damage, it causes distress on the part of the vehicle owner. That makes it a problem. Period.
Wondering whether or not your engine is going to sound like a typewriter in a kettle drum when you start it can make some reluctant to purchase. GM has a way to go as far as aural stimulation at start-up.

[jlp16au]

Does the TSB (#01-01-39-004A ) cover the 2003 silverado as well?

When I am driving at highway speeds the ac blows cold. Using a thermometer I have measured vent temp around 45-50 deg. When I am parked I measure vent temperatures around 70-75 deg.

If this TSB does not cover my truck does anyone know what the problem might be?

I previously had a bad low pressure switch and that has been replaced.

Thanks