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2008 Lifter problem- What happens if keep driving it? (long distances)

Bonzohansen said:
$4k?  nah, i'll do it myself.  Get rid of it, get a new cam add a little power for towing.  Maybe get the heads cleaned up while they are off.  Good times.
Trying not to jinx myself, i don't really mean this next part because of the cost, but a small part of me hopes to get the ticking so I can tell the wife I "have" to get a new cam & AFM/DOD delete..
 
BainMan said:
Trying not to jinx myself, i don't really mean this next part because of the cost, but a small part of me hopes to get the ticking so I can tell the wife I "have" to get a new cam & AFM/DOD delete..

I keep eyeballing 6 liters.....
 
The #6 cylinder was bad lifter. Cam and Cam bearings bad, Had new engine (GM rebuilt long block) installed at GM dealer. Needed new water pump, cam sensor and of course oil and coolant.
Total including tax was $8100 and has 3yr 100,000 mile warranty. Beats taking it in the shorts for an otherwise perfect vehicle with only 70K miles, all new brakes, belts. pulleys and tires
>3/4 tread. I have always intended to keep this truck until I die and as such have kept it in great condition with light use. I love this truck!
Has anyone had any luck talking to GM/Chevrolet about sharing in the cost of an incorrectly engineered engine (specifically the lifters that have been failing)? I think that pick-ups use the same engine. I have spent 3+ months trying to work my way through Chevrolet Customer assistance (they really are not in place to "assist"customers, but rather to say no to all requests. Last conversation today, I again requested escalation to a VP and they denied it.

Last conversation they said that the engine should have been disassembled to confirm the lifter and damage. I told them that engine went back to GM engine rebuild and they could check with them on the tear down and damage by my VIN number on the engine. They said that they can't call GM rebuild, cause they don't have their number? Hey, I know this vehicle is far out of warranty. But when you design bad parts that make an engine fail, wouldn't you think they would have some pride in their product?
 
Unless you like giving your money away never use a dealer. You can get the same work done at a good mechanics shop for far less and have same warranty. And taking to a dealership doesn't mean you get guaranteed best service. For a truck as old as these you can get a junkyard engine for far less and have it installed. Likely in the $1500 range depending on the motor. And junkyards give a 30 day warranty that should tell you if its shot or not. Using a dealer motor on an AFM equipped engine and you still have the AFM which will cost more to remove properly than having gotten a junkyard motor in the first place. Dealers generally have huge markups on parts and excessively charge on labor. I never go to one unless its something I can't get done anywhere else. Even just having your old engine removed and having it replaced with a locally rebuilt one (without the AFM) you are going to be significantly cheaper than a GM crate engine. A little late now but words for thought.
 
Unless you like giving your money away never use a dealer. You can get the same work done at a good mechanics shop for far less and have same warranty. And taking to a dealership doesn't mean you get guaranteed best service. For a truck as old as these you can get a junkyard engine for far less and have it installed. Likely in the $1500 range depending on the motor. And junkyards give a 30 day warranty that should tell you if its shot or not. Using a dealer motor on an AFM equipped engine and you still have the AFM which will cost more to remove properly than having gotten a junkyard motor in the first place. Dealers generally have huge markups on parts and excessively charge on labor. I never go to one unless its something I can't get done anywhere else. Even just having your old engine removed and having it replaced with a locally rebuilt one (without the AFM) you are going to be significantly cheaper than a GM crate engine. A little late now but words for thought.
In older days, I would have rebuilt it myself. Now, I'm older and not so motivated. I trust the GM rebuild process and so went that way, even though expensive. I plan to keep this AV for the rest of my days, so just spent the money. I do think that GM should take some responsibility for a very poor design of the AFM (DOD) system especially the lifters (two or three redesigns). One can buy a plug-in that eliminates the 4 cyl mode.
 
That is your choice of course. And programing the AFM out may reduce its chances of blowing up the engine but certainly not remove those chances 100%. I hope the dealer gave a great warranty for that price.

And GM won't agree that it is a poor design because the vast majority of those engines last well over 100k before they have problems as long as the owner uses high quality synthetic oil and change often. Never mind the same motor without the AFM would be much more durable.
 
That is your choice of course. And programing the AFM out may reduce its chances of blowing up the engine but certainly not remove those chances 100%. I hope the dealer gave a great warranty for that price.

And GM won't agree that it is a poor design because the vast majority of those engines last well over 100k before they have problems as long as the owner uses high quality synthetic oil and change often. Never mind the same motor without the AFM would be much more durable.

Dealer on a GM rebuild has 3 year 100K warranty. My AV used Mobil-1 oil and filters its whole life. I have had 31 GM Vehicles and NEVER had an engine failure, even the Corvettes which were driven with purpose to over 100K miles with not even oil usage. I am disappointed in this engine and with GM for not recognizing this issue on pick-ups, Tahoes, Yukons, and of course Avalanches. They obviously knew about the design issue or they would not have redesigned the lifters multiple times. I just think they should share in the cost. Please, someone, share a phone number/email address of an appropriate VP that I can contact.
 
2007 and 2008 model years were especially bad. When GM filed bankruptcy they changed a lot of things. This is the "NEW" GM now so don't expect them do do anything about anything prior to 2010 especially. My 2009 Cadillac CTS used about a quart of oil every 700 miles. This was within their "acceptable oil usage". And there are a number of problems with the 2008-2009 CTS cars such as poorly engineered AWD driveshaft and a timing chain that doesn't last much more than about 30,000 miles in MANY of the vehicles. GM had a special agreement on the 2008-2009 with the feds about the timing chain where they replaced it with a better quality chain up to 100,000 miles and 10 years. There are many of those cars still out there that are now no longer covered that will have that $2000 job needing to be done. GM has seemingly greatly increased their quality in many areas since the bankruptcy. Good luck in your journey but don't be surprised to reach a dead end. The AFM problem in these engines is well known but GM to my knowledge doesn't even acknowledge there was an issue.
 
2007 and 2008 model years were especially bad. When GM filed bankruptcy they changed a lot of things. This is the "NEW" GM now so don't expect them do do anything about anything prior to 2010 especially. My 2009 Cadillac CTS used about a quart of oil every 700 miles. This was within their "acceptable oil usage". And there are a number of problems with the 2008-2009 CTS cars such as poorly engineered AWD driveshaft and a timing chain that doesn't last much more than about 30,000 miles in MANY of the vehicles. GM had a special agreement on the 2008-2009 with the feds about the timing chain where they replaced it with a better quality chain up to 100,000 miles and 10 years. There are many of those cars still out there that are now no longer covered that will have that $2000 job needing to be done. GM has seemingly greatly increased their quality in many areas since the bankruptcy. Good luck in your journey but don't be surprised to reach a dead end. The AFM problem in these engines is well known but GM to my knowledge doesn't even acknowledge there was an issue.

If you remember, redheadedrod, I also had a 2006 Cadillac CTS a while back.

We bought ours with 35K miles and it used oil at an alarming rate since the beginning.

As we later discovered, a poorly designed PCV system was mostly to blame for the oil consumption and many owners had resorted to installing oil catch cans to help keep that oil out of the intakes.

Our CTS engine got it's timing chains replaced at around 80K.

At just over 100K miles, the carbon buildup on the upstream side of the intake valves, caused by the heavy consumption of oil into the intake and the design of the GDI engines in general, caused a burned intake valve.

At that time, I had both heads removed and repaired.

Shortly afterwards, we traded that car off.

Having not completely learned my lesson, we traded the 2006 CTS for a 2012 GMC Acadia.

We have since learned that the timing chain issue with those engines is still an issue at least up through the 2012 model year that we bought.

Knocking on wood, so far the timing chains have not shown any problems with our GMC, but I change the oil, as recommended by many owners, at a much accelerated rate.

This engine does not seem to have quite the appetite for engine oil that the CTS did.

But, I used my bore scope to examine the upstream side of all of the intake valves when I had the intake plenum off to change the spark plugs and every one of them showed a lot of carbon build up on the intake valves.

I rarely have to add any oil between oil changes now.

However, these engines are prone to random misfires, which I attribute to the carbon build up in the upstream side of the intake valves.

That appears to be a common problem with GDI (Gas Direct Injection) engines of many brands.

Upper intake cleanings seem to be recommended by many owners and I am sure professional cleanings may be more effective than DIY solutions.

We currently have 150K on the GMC, but I honestly do not see me being able to avoid some expensive repairs on this engine if we decide to try to keep it for a while.

The shame of it is a lot of modern vehicles use GDI technology, so it is likely that we would be trading for the same situation if we moved on to something else.
 
We too share the joy of direct injection at our household, wife has a Traverse with 189k on it.

Story time: The water pump went out June 2019 and the Mrs drove it the rest of the way home, but she did make it home.. The motor was still pinging loudly when I got home 20+ minutes later, but nothing catastrophic appeared to happen...

Anyway I got lucky and just changed the valve cover gasket, intake manifold gasket, spark plugs tube seals, spark plugs and coil packs, (plus water pump) but while I was in there I spent a couple evenings cleaning out the intake valves because the buildup was so bad , some places it was thicker than 2-3 stacked quarters... I tried a bunch of things but what ultimately worked best for me was a long screwdriver and just get to scraping.. Blow out the port & shop vac what comes out. Once the largest portion is out use some intake cleaner to loosen up the remaining and clean out the rest with cut shop rags or whatever. Oh, and make sure to turn the motor to completely close the valves as you go.

The valves should have regular cleaning, perhaps annually, but I'm not up for it yet so maybe this winter I'll get around to seeing how they look after 10-15k miles since the last cleaning..
 
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The 2012 CTS came with the LFX which was the most advanced version to date. Much less oil usage. The Timing chain issue was only in 2008-2009 engines. They used a different timing chain starting in 2010. Because there are three chains they do stretch more and will have to be replaced before the rest of the engine wears out. However a standard LS engine only has 1 chain of much smaller length and will stretch far less over its lifespan which is why you don't hardly ever hear about an LS engine that has had its timing chain replaced due to stretching under normal circumstances.

And yes there is intake valve coking on my car. I was told about a cleaning solution I am trying to track down. The idea is you pour some diluted liquid into the intake runners after pulling out the plugs. You let it sit over night and the next day by hand spin the motor over to run this stuff out and flush it out with distilled water. Note that it will make a mess...Unless you somehow connect tubing to each plug hole and run it to a catch pan.

When done use compressed air and try to blow out each chamber as best as possible. The guy said he did it with his engine and it looked like new with no scraping needed. Of course when you are done you need to replace the intake gasket. But we are getting off track. And yes ALL DI engines have this issue due to how they are setup.

Someone I am talking with is in the process of moving the PCV discharge to his exhaust pipe past the Cats... This will prevent the intake valve coking all together but still give the gas a place to go and removes the need for an oil catch can. Apparently its a trick some racers use to keep the intake clean. This would work in pretty much all vehicles.
 
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