I don't know why people put so much stock into the axle ratio, don't forget you have at least 6 gears in-front of that... not counting the transfer case if you're in low.

or in the 2015 (now) 8 gears...

axle ratio is only one piece of the final drive ratio... which would give you a more accurate way to measure these vehicles across years.

Combined with the fact that MPG is an awful measurement... it should be Gallons / 100 miles.

Why We Should Measure by Gallons per Mile, Not Miles per Gallon - Popular Mechanics

Actually, it should be Liters / 100 Kilometers, but that's another story.

 

When I purchased my 2009 Chevrolet Avalanche, I always intended to drive it until it dies. Little did I know it would die at 72,000 miles. What kind of product is GM making these days?

I purchased an extended 60 month, 100k miles warranty on my truck. 40 days after the warranty expired, I was driving down the highway and then my service traction control and stabilitrak alarms are going off and a loud clicking started coming from the engine, and my oil pressure dropped to about 20-30. I immediately pulled over into a gas station, checked the oil, which seemed OK (maybe a bit low), so I put a quart in. This returned the oil pressure to normal but the engine was still clicking; had no clue what the issue was.

I attempted to get to my destination (about 20 miles to go) and kept it at 55 mph. Made it into town and the clicking turned into a chugging like the engine was about to stall. There happened to be a GM dealership at my exit so I pulled in and had it diagnosed. The dealership told me there was a cylinder misfire, which caused the Traction Control and Stabilitrak to shut off. The fuel was burning rich, causing excessive backpressure on the cat and making the engine want to stall. It was a weekend, so I had to wait for a tech to get in the following Monday to run a proper diagnosis, but they thought it was the cam.

It took until Wednesday and I received a call indicated the cam and lifters needed replaced. Initially they quoted me $5,000, which seemed very excessive. I call them out on it, was put on hold for 30 seconds, and then told they talked to GM and GM was willing to cover 50% bringing my out of pocket expense to $2,500. Anytime someone drops the price in half immediately, I start to question what's going on. After a little prying, I was able to get a work order out of the dealership with a parts list. (The truck was stuck at a shop 150 miles from my hometown, so I had to do all of this over the phone).

I called my home dealership, explained the situation and what happened. They were also familiar with the cam/lifter issue...odd that all of the dealerships know about this yet there is no recall! Anyways, they said based on my extended service warranty and work needed to be performed, the total job should cost $3,000 with $1,800 covered by GM and $1,200 covered by me.

My total costs to get the issue resolved are: $250 Diagnostic Fee for Dealer #1, $350 tow charge to hometown, $1,200 repair bill from Dealer #2. $1,800 all in, which was still cheaper than the quote from Dealer #1. I also didn't want the truck to be too far from my hometown in the event they got into the repair order and other miscellaneous charges started popping up. Luckily this didn't happen.

The cam and lifters have been replaced with supposedly no damage to the engine block. I don't like that it's been torn apart and put back together, but that's the current situation. At least the work comes with a 12k/12 month warranty. This leads me to the following:

Has anyone had any issues with the truck/SUV for a cam/lifter replacement only (no new engine)? Any recommendations on keeping the vehicle v. selling it while it still runs?

Unfortunately, due to the extremely poor quality experience, I probably will not be buying another GM Truck. It's sad the GM can not own up to this design flaw and offer a recall for their mistakes. They consistently offer recalls on their low margin vehicles and do nothing the maintain their high margin truck clients. I tried pricing out a new GM truck and it's $50-60k for something comparable to what I have now. The Work Truck edition starts in the mid $30's...why does GM think they can get luxury car prices for a product that can't last 5 years? Correction, it can last the full 5 years...just waits to die until right after the warranty expires.

***Apologies for the redundant post, newbie to the forum. I removed the old one as this post is more complete.

 

Salaman,

GM is not owning up to this defect. I have been tracking this for over 3 years, and your unfortunate story is similar. It is strange you were only down 1 quart instead of 2+ quarts like others. Normally, the engine is totally "shot" when you get the first signs of trouble. Others have been told a GM refurbished engine would cost $6000, and you would pay 50 % of the cost. Your extra warranty likely had some impact on your out of pocket cost.

The sad part of your story...is that you may have the same problem (or worse) in the future. Active Fuel Management (AFM..in vehicles from 2007-2009) has caused excessive oil consumption. My recommendation, is to:
--Wait for something terrible to happen again,
--and then get a GM replacement engine ($6000...and hope they only charge you 50 % of the $6000).
--have a "tune job" done on the replacement engine to eliminate AFM.

As of today, you could get a "tune job" on the old engine to shut off the AFM in the computer, but this might complicate things with GM, because they will know you modified the computer and get pissy about this. A "tune job" will void a new car warranty. But you now have a 12 month extra warranty for your $1800 expenditure, and I would stick with the plan.

GM has Americans by the nuts on this one...and have screwed many. Keep a close eye on your oil level. The temptation is to get rid of the vehicle. I would not rely on the vehicle for a big trip across the country, and would use a different vehicle for such trips.

But, when/if the engine is ruined in the future and a GM refurbished engine is offered to you, then I would have a "tune job" to eliminate AFM regardless of any warranty they offer at the time, since we have heard "it will happen again...due to AFM".

It appears GM has fixed the AFM problem in 5.3 V8 engines after 2009! 2007 vehicles were the worst with AFM problems and excessive oil consumption. Many of the posts for this problem occurred a few years ago, and are apparently unavailable for viewing. I remember reading explanations about "soft cylinder rings" and "improper cylinder cooling by AFM shut off of the 4 cylinders" causing this problem.

Ford and Dodge have had a number of problems as well, but nothing like the AFM problem. Just go to CARCOMPLAINTS.COM and you will be educated beyond belief...regarding Chevy's, Fords, and Dodge trucks...for the particular year you are investigating. My son has informed me the Honda Odyssey has AFM in his 2009 vehicle.

I bought a used 2006 Chevy Suburban just to avoid the AFM problems when AFM was introduced on 2007 5.3 V8 engines in the full size truck line of vehicles. If you have not had other problems with the vehicle and you can endure implementing my above recommendations, you will save money.

I just can't see throwing another $50/60 thousand at a new vehicle when the old vehicle is only 6 years old. On principal, I also would not reward any car manufacturer that expects Americans to pay for their bad design (AFM)...by buying another new vehicle from them.

Whatever you decide to do with your GM vehicle, you have my sympathy. The above recommendations represent my thoughts on "making GM accountable for what they have done" while saving money for those unfortunates who have suffered from buying a bad GM vehicle with AFM defects.

 

I have an 08 sub with 103k on the
clock and am lucky as not to have the oil consumption issue. But I an curious about the the tune to negate the AFM.
Would anyone consider that?

 

Thanks roknwoe. Quick update, the Dealer was able to pass the tow charge off to GM as well, which was a nice surprise. I was all in for $1450 after that one. You are correct, the extended warranty did help in the cost sharing on GM's part.

My main fear, as you have highlighted, is that the engine goes out again in 20-30,000 more miles and GM doesn't offer any assistance. I asked both dealers that looked at the truck several times about any damage to the engine block, and they both said none. I'm guessing if it was under warranty, they might have said yes and passed the cost on to GM and had the engine replaced (which I would have preferred). But since it was out of warranty, I get the patchwork fix...which doesn't leave me with a warm fuzzy feeling.

Right when I get the truck paid off and get excited about a virtually young vehicle with no car payments, this has to go and happen. I tried to research recalls on this issue and all of the forums talk about GM needing to issue one, but there doesn't seem to be any traction on getting one started.

A few questions for the forum:
1) Has anyone had only the cam/lifter replacement? If so, any recurring issues and how many miles until that started?
2) Has anyone disabled the AFM? Does it cause any lingering issues within the engine?
3) Anyone know how to petition for a recall on this?

I want my 1985 Silverado back!! I sold that with +200,000 miles on it and it still ran fine with the occasional starter or alternator replacement. It probably costs more than my Avalanche is worth now.

 

Salamon,

The cam and lifters problem does not sound familiar. I picked up on the fact that your oil pressure was down and you were 1 quart down on oil.

There are lots of references on "disable AFM" on Google. You can also pay special shops to do this.

However, once the "damage by AFM is done" (your engine is burning oil such as 2 quarts per oil change interval), forget about the tune...since it is too late.

It has been reported that AFM will not engage...if you run your truck in 5th gear versus 6th gear on an automatic transmission. The time to do the "tune" is way prior to putting on lots of miles. If I owned a brand new 2007 thru 2009 5.3 V8 Silverado, I would not get the tune,but instead run it in 5th gear until the engine warranty expires, and then get a tune, and start running it in 6th gear.

I know this sounds strange, but would one prefer to get screwed by GM and end up paying up to $6000 for a new Goodwrench remanufactured engine when the original engine starts to burn 2+ quarts per oil change?

Others have tried the "Seafoam" cleaning treatment...in hopes of "freeing up the clogged rings" and "reducing/eliminating" the oil consumption problem. Some say it works, but I am not convinced. I myself use Seafoam in the oil during an oil change for the extra lubrication/cleaning properties, and Startron gas treatment in the gas for potential bad gasoline, such as "ethanol problems in the gas station gas". I try to buy only unleaded gas with no ethanol added.

From what has been reported, using a better quality of oil will not stop/prevent "excessive oil consumption due to AFM". (oil such as Mobil 1 synthetic).

If your engine (cylinder walls and piston rings) have truly not been damaged, I would:
--change oil with the correct proportion of Seafoam added;
--run your vehicle in 5th gear until the 12 month warranty expires,
--and then get the tune and run it in 6th gear.

You should be able to see if AFM engages (or it doesn't engage) in 5th gear, since I understand there is an indicator you can select on the dash which indicates "4 cylinder" or "8 cylinder" mode.

It has been reported excessive oil consumption starts after about 50 thousand miles on some of the 5.3 V8 engines. No one knows exactly "how many engines" have this problem...since GM is not going to publish/report this damaging information.

 

Is this really true, or is it simply because the bulk of the 2010 and newer fleet that's on the road hasn't racked up enough mileage to expose the problem?

I'll be in the market soon for a truck for my daughter. She's currently driving my 08 Burb, so I want to get her a GMT900 because it's familiar to her. I was going to go with an Avalanche or half-ton Silverado/Sierra, but this AFM crap has me totally scared of used 5.3 motors. Top candidate right now is an 07-09 Escalade with the 6.2 (and no AFM), with second choice being a 3/4 ton pickup.

Sucks, too, because I also have an 01 Burb with 193K miles on it with the original 5.3 engine and transmission. She's been ridden hard and put away wet many times, but the engine still runs like new. Only GM could screw up such a great motor.

 

To: InTheBurbs

I checked CARCOMPLAINTS.COM for a 2010 Silverado with a 5.3, seeing there are lots of these being sold, and "if" there are still problems, there would be a rash of people complaining about oil burning. I only found 3 "personally submitted" complaints (versus TSB "governmental logged complaints"), and here is a person's remarks regarding their oil burning problem that occurred at 33,000 miles:

--At 33890 miles this truck started using oil. The dealer where I purchased the truck has performed all of the required maintenance. The truck is using up to 2 quarts of oil in between oil changes. I have the oil changed every 5000 miles and I use Mobil 1 synthetic oil. The dealer has performed the recommended fix under TSB01-06-01-011G. Per the TSB the accepted rate of oil consumption is 1 quart in 2000 miles. I do not use the vechile for a business, only personal use and most of the mileage is on the road. I do not tow a trailer or carry excessive loads in the truck . THE TRUCK FOULED A PLUG AT 46506 MILES. I have contacted GM Customer Relations and they are standing on the TSB that 1 quart every 2000 miles is acceptable and I do not have a problem. I feel that using this much oil is a problem. This has really turned me against buying another Chevrolet. I have owned Chevys in the past and had no problems. Maybe "Government Motors" GM has a problem with this engine ? Does anyone recommend a further course of action ?

- carlsc, North Charleston, SC, USA

Three complaints is very low for a single model year for a 2010 Silverado...compared to the rash of complaints for the 2007 Model year when AFM was introduced on the full size truck vehicles. I also reviewed the TSB complaints, and there were relatively few that could be "pinned on AFM problems".

I grant you that a 2010 model would normally not yet have the necessary mileage when AFM becomes a problem...but one would expect to at least see a pattern of AFM in some of the 2010 vehicles. The above story is a 5.3 Silverado with only 33k miles.

Do I trust even 2010 thru 2012 Chevy's with the 5.3v8 with AFM? Would I buy one? My answer is NO! I have shared the information learned from others on this topic with my brother who is looking to buy a new 2014/2015 Sierra/Silverado. And he is somewhat scared to spend $40k+ on a new AFM vehicle.

Similar to an adulterous mate (analogy only), once you have been burned to the tune of $40-$50k, one is very leary to "roll the dice" on the same brand again!

 

with 90,000 miles on the clock on my 2009 5.3 w/AFM, the only time I was significantly low on oil was after towing a 6,000 lb trailer all summer...

So I'm going to say that my 2009 appears to be working fine... from an oil consumption standpoint.



Also, this doesn't burn any oil... --> The 691 Horsepower ?Tesla Model S P85D Does 0-60 In 3.2 Seconds

 

I am really dissapointed in GM, I am driving my fourth chevy tahoe and have had nothing but positive things to say about chevy and tahoes until now. I was really excited for the new tahoe to come out with the options i have been hoping they would incorporate into tahoes. I have driven all four tahoes from 120k to 225k with minimal issues on all of them. I am now driving my 2007 tahoe with 125k miles or was driving until a few days ago when my engine went out due to active fuel management issues. I drive around 20-30k miles a year and am very pro active on maintenance to ensure a long life on my cars. I change oil every 3k miles and flush transmission fluids etc. come to find out all of my proactive maintenance was for nothing since there was nothing i could do to prevent my engine going out due to a manufacturing error. I was surprised to hear that there was so many similar issues with this on this car. i originally took it to my mechanic who identified it within 5 minutes and said it was the 5th one he has seen this month and to take it to the dealer to see what they could do. upon showing it to the service dept i was shocked to hear that the service manager had never heard of this issue before and it was just bad luck, a new engine would cost $6,300. I then took to this forum and saw that a few people had some luck with GM helping out so i called GM corporate customer service. after 3 days they told me i was out of the paramaters for them to help. THAT'S BS, i could understand if i neglected the car and wore it out but this seems to be unpreventable on all 2007 to 2010 chevy tahoes. I didnt ask them to pay for it i simply asked for them to split the new engine with me or get me the engine for cost. To say the least i have lost all faith in GM products which really bums me out as i have loved and relied on them for the last 20 years.