I KNOW THIS IS A VERY LATE ENTRY, BUT FYI, IF YOUR 5.3 HAS THE 706 HEADS (STAMPED ON THE OUTSIDE OF HEAD, EASILY FOUND ON THE RIGHT SIDE OF PASSENGER HEAD) THEN THEY ARE CASTECH HEADS MADE IN CHINA. POOR CASTINGS. THE POROSITY OF THESE HEADS ARE SIGNIFICANT! WITH ENGINE UP TO TEMP PULL VALVE COVER OFF AND USING A BLACK LIGHT YOU CAN SEE ANTIFREEZE SEEPING THROUGH THE PORES OF THE HEADS, ALSO CRACKS IN HEADS AFTER SEVERE OVERHEATING PROBLEMS. REMEMBER BULLETIN #06-06-01-019B IS ONLY WRITTEN TO INFORM THE "GM TECHS" OF CONDITIONS THAT MAY OCCUR AND WHAT TO DO.MY 04 HAS 258,00 MILES AND I HAVE BEEN CHANGING THE OIL EVERY 3000 MILES AND CHECK BOTH THE OIL AND ANTIFREEZE LEVELS EVERY WEEK TO COMBAT THIS ISSUE SINCE GM WILL NOT TAKE RESPONSIBILITY. I HAVE HAD TO PULL OIL PAN ONCE DUE TO A PLUGGED PICKUP SCREEN FROM THE BUILDUP INSIDE OF OIL PAN. BUILDUP HAS BEEN MINIMAL SINCE DOING THE FREQUENT OIL CHANGES. I HAVE BEEN ABLE TO AVOID ANY COSTLY REPAIRS BY DOING THESE THINGS. A ROYAL PAIN BUT NOTHING ELSE BESIDES UPGRADED HEAD REPLACEMENT. DOES NOT NEED AN ENGINE DUE TO THIS ISSUE BUT A RECON ENGINE MAY NOT BE MUCH MORE THAN A NEW HEAD REPLACEMENT.

We also have a 2004 Tahoe with the same exact problems stated by other Tahoe or GM truck owners on this page. Burning oil, white exhaust and water seeping out of the exhaust and overheating. I took it to Chevy dealership. I spent $7,800 because everything they tried did not work, I replaced the water pump, thermostat, a bunch of parts within just a 2 month period. My truck only had 61,000 miles. It should NOT be experiencing these problems.

Just recently, I meet a gentlemen who used to work for Chevrolet and he says that "this is a common problem in the GM trucks". He never saw my truck but says that by replacing the "intake manifold gasket" should fix the problem. I noticed that someone else commented on replacing that and it worked out. The gaskets heat up and cannot hold the liquids and they become mixed. Ex. anti-freeze into your oil, he says this is very bad but if caught on time, it should run like it never had a problem. Now if you use water instead of anti-freeze, the water condenses and if you open your oil cap and there is water on the inside of the cap, you know this is definitely the problem. If not taken care of, the water eventually rusts the inside of the motor and you are screwed.

Of course, Chevy does not want to take responsibility because this is a factory defect, they just cannot come out and say it because they will have a lot of repairs to do at no cost to the vehicle owner.

I am getting the intake manifold replaced this weekend and I will update you all on how it went.

I bought a "Certified" 2004 chevy tahoe through a dealership. I have only driven it about 26,000 miles and it started smoking. There was a gurgling sound behind the dash. I checked to see if there was an air pocket in the system and realized there was a lot of coolant missing. It was about a gallon and a half low. I took it to the dealership to confirm it was only a head gasket but to my surprise it was a manufactures flaw in the casting of the head. Due to the porosity of the head it may seep coolant through the metal. It was also noted Castech was the culprit.

Bought this car for realibility at 50k miles. Just started using excessive amounts of anti-freeze. Just found out from the dealership that I now have two cracked heads due to the CASTECH HEADS!! Not sure if Chevy is going to Reimburse me yet. Been on the phone with them. I think this is their problem they knew about the CASTECH HEADS cracking. My other car is a 1999 F350 Spelled F. O. R. D. and has 258000 miles and all I do is change the oil. I bailed GM out with my tax money, they should bail me out!!!

Purchased extended warranty, problem occured right after warranty ran out. Tahoe started overheating & using antifreeze. Then started burning oil. I have had to add oil & antifreeze to it on a regular basis. Repair costs $3000 to replace engine. Took it to 2 Chevy dealerships & both times the service mgr knew exactly what was wrong without even touching my truck. Got the exact same response of... "this has been a common problem with these engines." Contacted GM & of course they acted like they have not heard of this. Loyal GM customer..... NO MORE!!!!

The 2004 Tahoe is a piece of sh*t. We have done all thr general upkeep on the car. I started noticing the car was running hot on night. The car started chiming and it said

ENGINE COOLANT HOT. So we pulled over to let it cool off. We added antifreeze the next day. The problem went away we thought ok cool it was just low on antifreeze. But as time pass by we were adding it more and more often. We also currently have a problem with the a/c. It blows cold the hot all of a sudden. We also replaced the speedometer early late 2008. I will never buy another Tahoe Chevy needs to get they sh*t together because people pay to much for these f*ck up ass trucks. The dealers they are no f*cking help either. But we plan to trade the POS Tahoe in early 2010

I had a 2003 Chevrolet Tahoe 4.8 L V8 with 327,000 miles and no engine issues. Due to an accident I had to replace this vehicle. I purchased a 2004 Chevrolet Tahoe Z71 5.3 L V8 with 111,000 miles. I haven't even put a tag on it yet, drove less than 5000 miles and noticed no radiator fluid in the reservoir and that I was burning oil. I had one message come up on the console stating "Engine Coolant Hot" and then it went away. No overheating on the gauge to any significant degree. It would appear that I am losing fluid and oil through the engine and exhaust. I am told it is most likely a head bolt, intake gasket, or head gasket, all of which would not be cheap to repair. And of course, it is out of warranty and no extended warranty. I will report the outcome later.

Not really sure of anything I can do other than complain. I just found out that It's going to cost me $4,000.00 for a brand new motor. My 2004 Tahoe is just now breaking in and now the motor is no good. Both heads are cracked due to it taking antifreeze when there were no leaks. I was also having to add oil even though I regularly change the oil every 3,000 miles. The gm person told me we would have to have a new motor and my Tahoe only has 78,000 miles. This is not why I bought a Chevy. I was under the impression they would last well over 100,000 miles. I guess not. Especially with the lovely price that comes with buying one. Can you say over priced cars that wont last?

Original owner of 2004 Tahoe. Overheated twice in last two months due to low coolant but no visible leaks. GM dealer says that coolant leaking internally due to cracked cylinder head. There is GM technical service bulletin confirming the problem is manufacturing defect causing metal "porosity" (fancy word for "it leaks") in heads from Castech. I've contacted GM customer service to request after warranty assistance to pay for this (though, at best, they will only pay 1/2). I'm a lawyer and because this is a confirmed manufacturing defect, I think this should be recall or at least fully covered by GM (let them sue Castech if they want).

Dilemma is whether to replace one or both. GM dealer wants $1800 to replace bad one and says he would not rec. replacing other. Independent mechanic says he would replace both and can do it for around $1500 to $2000. If GM doesn't pay, guess I'll go independent but if I do, I won't buy GM again. It may be out of warranty but this is clearly a premature failure due to manufacturing defect.

Update from Sep 4, 2009: To update, GM paid for 1/2 of cost of replacing one cracked cylinder head. I asked to replace both since it is confirmed defect but refused to replace second because it was not leaking, Said if it cracked, they would take care of it then. One year later, August 2009, tapping noise on cold start, took it in. Other cylinder head cracked but worse, additional damage to cam bearings and rod bearings. Need a new engine which will be $5000 or more. I have call into GM, been waiting four days for response. Nothing yet.

Update from Sep 10, 2009: Chevlrolet now says they will not pay for ANY repairs, even tho (1) it is known defect, (2) they paid 1/2 to replace one-side cracked head last year, (3) told me that if the other head cracked they would take care of it, (4) due to cracked head, I need a new engine.

I bought my Tahoe used 1 year ago in May 2007. In May 2008 I started hearing engine noises (lifters rattling) and white smoke was occasionally coming out the exhaust on cold starts. We had purchased an extended warranty so we took it back to the dealership and they replaced an O-ring on the oil pick up and intake gaskets. They had it for 3 weeks. The warranty company paid for it and that stopped the noise for 2 weeks then it was back again worse than ever. I was furious and took it back to the dealership and they informed me they no longer had a tech to work on it so they sent it to a dealership 35 miles away. They had it for 2 weeks and thought that maybe the oil pump was cavitating but they weren't for sure. The warranty company refused to pay them to do exploratory work. Great! So I told them to put it back together and bring it back home and I would drive it. No noise for 1 week then it sounded like it was going to knock itself to death. I took it to another local dealership and they handed me a bulletin (#06-06-01-019B) after they ran my vin # and said this is what we think is wrong with your Tahoe. It showed a picture of a head with a Castech log on it and were the crack could be found on it and that my warranty company would pay for it. I thought what did this have to do with my engine noise. But I agreed to let them take it apart. They called the next day and said that my Tahoe did have that brand of heads and that they were waiting on the warranty company to send an adjuster out to look at it. I waited for 2 days and did not hear anything then my husband calls me and tells me the warranty adjuster had just called him and told him that it wasn't there responsibility because it was bad heads put on by the manufacturer. What? I had purchased the best warranty through Vehicle One ($1,500.00) why did it not cover it. I read the warranty and sure enough cylinder head that are defective are not covered unless damaged due to lubricating parts. What now? So, I called the dealership back and he said he was just fixing to give me a call. He quoted me prices to replace the engine $6400.00 or $4400.00 to replace heads and other bad parts. I about had a heart attack. I said I would have to talk it over with my husband and call him back. I talked to my husband, who is a part time mechanic, and we agreed to have him do it and just void the warranty since it wasn't going to help anyway. I called the dealership back and told him to put it back together and give me a phone # to Chevrolet because what part of this is my fault! All I did was purchase a used vehicle that should not have had bad parts placed on it at the factory. He said wait a minute a was just going to call them myself. When I went over that afternoon the dealership stated that they had talked to someone @ Chevy and that they would pay for 1/2 of the bill to keep us in good standing as GM buyers. I agreed somewhat reluctant to relace heads and parts only. I picked it up a week later and they handed me a bill for $3486.23 and told me I could pay $1750.00 and we would be even. I wrote out the check and haven't had a problem since. I did call Chevrolet @ 1-800-222-1020 and they said that they have never heard of such a bulletin and that they have never heard of any problems and they weren't liable for any reimbursements. I told him that I just wanted them to note my complaint. So think twice before you purchase any used vehicle or buy an extended warranty without researching first.

We purchased this Tahoe from our local Chevy dealer near our home about a month ago. A week after we got it home, my husband noticed it needed coolant as the reserve was very low. We thought the mechanics that do the inspection before leaving with it off the lot, just simply forgot....so up the auto parts store we went to pay $20 for a bottle of GM coolant. A week after that, my gas mileage went into the toilet. I thought I got bad gas because I had went to a local gas station that was .20 cents cheaper than anyone else at the time, and assumed that's what was happening. We were getting anywhere from 16-19 MPG when we first got it, and it had gone down to 13-14 MPG. Then 2 weeks later, I put premium gas in it thinking maybe that would clean it out and get us back into the better gas mileage and all of a sudden, I was down to 12-13 MPG! I was freaking out! So 3 weeks later after purchasing the truck...we were worse off than when we had gotten it...so I wasn't sure what to do. Then earlier this week, we definitely knew something was wrong. I was getting a message on my dash, stating to "Check Oil Level". Now I was starting to really get worried...so I drove it up to the dealership. Well, of course they were too busy to get to it, but they were able to identify whether it was really low on oil, or if it was a sensor issue due to the fact that "everything" on this truck is electronic. They determined that the oil level was very low. They never checked anything else, and just topped it off, and asked for us to bring it back in 1000 miles to see where it sat. We had only driven it 1000 miles since we had it. I went home and it took all but 5 minutes for me to get aggitated about it, and I turned right back around and went back and talked to the sales manager. He had me bring it in first thing the next morning. That night (before I brought it back) my husband checked the coolant again out of curiosity and found the reserve was almost empty again! There was no leaks anywhere of oil or coolant, so he checked the oil....yeah, bright ass yellow. He knew what was wrong with it now. The funny thing is, the truck was still running great, and purred like a kitten. No engine noise or hesitation at all. I went up to the dealership with it the next morning and I left it there and got a ride to work. I got a call later that day telling me that I had two cracked heads and a blown head gasket. They said it was from a casting defect. They acted like they were covering it as a dealership courtesy, when in actually GM was covering it as goodwill. Apparently the previous owner had logged a complaint with GM for prior problems with the cylinders. We were fortunate that we received the work under warranty, because we were just over our 30 days of purchase, and there was only a bulletin on the our particular motor through GM, not a recall, for the bad castings of these heads. But it is a known problem and they actually admitted it and addressed it which I thought was awesome. I'm sure the large dealership relationship didn't hurt either, and the fact that we just bought it. But then...I went to pick up the truck yesterday, and the dumb mechanic argued about replacing the thermostat and I asked about making sure the oil filter was replaced because the system had been contaminated....he refused to change the thermostat because it was not in the same area of the engine and he said it was fine, and he said the oil filter didn't need to be changed because he drained it and cleaned it out. I'm a woman, so it wasn't hard to convince me when he's been doing this for 30+ years. Well, my husband was furious when I got it home and told him that. Not to mention my oil pressure was at 25 idling, and only got as high as 40 while driving after the repairs. I didn't know any better. He made me bring it back up the next morning. I told the dealership that he demanded the oil and filter be done again, and we would pay for it if we had to. Sure enough, the filter was completely full of sludge from the contamination because you can't filter out coolant from oil, it turns into a thick sludge. They changed it and they didn't make me pay for the oil and filter change. Immediately, after changing the oil filter, my lowest oil pressure was 40, and only got as high as 55 today while driving it if I was accelerating. That's where it's suppose to be. Geez....what a hassle. Actually, they should replaced the thermostat also, because usually it doesn't take much to toast it when the engine temp gets hot enough with that kind of problem. I still didn't get that out of them yet. I'm not happy at all about this. We really thought we did our research on this year Tahoe to make sure it was a reputable vehicle to buy, and we didn't find anything about these kinds of problems. The carfax history report didn't even show anything about the cylinder work the original owner had done to it either, so beware if you think those reports tell all! I don't know if I'd ever buy another Tahoe. I'm almost scared about driving it now, fr fear something else is going to happen.