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Posted (edited)
8 hours ago, CamGTP said:

I think we are on thread 3 or 4 about this now lol

Yeah, it has been circulating a lot. While it gives me some hope that GM will do something about it, the reality is our '21 Silverado will probably need a 2nd set of equally bad replacement lifters before they A) actually issue a recall and B) actually have parts inventory to perform said recall.

 

I have a feeling that it's too big of a problem for them to fully address for current owners and they don't view it as a safety issue, so they're just going to let everyone run to failure and repair as-needed. Especially if the vehicle is out of warranty, lifter repairs are a huge revenue stream for the dealer service departments and I'm sure they'd rather make money than lose money doing it for free.

 

I'd rather have a carbureted 350 V8 that makes 200 HP in my truck than the L84 5.3 at this point. I can't wait to trade it in.

Edited by voided3
Posted

I would love to see GM respond with at least a 100k mile drive train warranty to those effected. I don't see GM doing anything but fixing the ones that fail under warranty. A lawsuit will take years to migrate through the system and the engines/owners effected will have cycled through by the time its over.   

Posted
8 minutes ago, WeGone said:

I would love to see GM respond with at least a 100k mile drive train warranty to those effected. I don't see GM doing anything but fixing the ones that fail under warranty. A lawsuit will take years to migrate through the system and the engines/owners effected will have cycled through by the time its over.   

That's the current escalation measure for those affected. Our truck got the extended component coverage on the engine (6 years, 100,000 miles) as one of the lucky early lifter failure recipients.

Posted
58 minutes ago, voided3 said:

That's the current escalation measure for those affected. Our truck got the extended component coverage on the engine (6 years, 100,000 miles) as one of the lucky early lifter failure recipients.

 Cool That's the least GM should do for you. This should be offered no questions to ALL effected trucks that fit into the TSB date range.. Unfortunately I made it by just days with a build date of 3/21/21.  

Posted

A extended warranty is probably the best we will get. To me there is a design failure in the DFM lifters. My thoughts are they discontinued DFM due to this failure as they try to plan the next step, while still being able to put product out. For me it would be nice if they replaced the lifters with a standard design and made corrections to the oiling system. It is such a shame they are destroying their reputation for dependable motors but the government is forcing their hand with the fleet fuel standards.

Posted
1 hour ago, Nutmeg said:

A extended warranty is probably the best we will get. To me there is a design failure in the DFM lifters. My thoughts are they discontinued DFM due to this failure as they try to plan the next step, while still being able to put product out. For me it would be nice if they replaced the lifters with a standard design and made corrections to the oiling system. It is such a shame they are destroying their reputation for dependable motors but the government is forcing their hand with the fleet fuel standards.

Completely agree, but they'll probably never deactivate DFM on existing vehicles as that's tampering with emissions control systems.

 

I honestly think if there were two identical L84 5.3 V8s, one with DFM and one with regular lifters like what they use in the 6.6 L8T gas V8, a 1 MPG gain could be easily had solely via an ECU retune on the engine with regular lifters. Even if it required 89 octane, it would be so much better.

Posted
2 hours ago, Nutmeg said:

A extended warranty is probably the best we will get. To me there is a design failure in the DFM lifters. My thoughts are they discontinued DFM due to this failure as they try to plan the next step, while still being able to put product out. For me it would be nice if they replaced the lifters with a standard design and made corrections to the oiling system. It is such a shame they are destroying their reputation for dependable motors but the government is forcing their hand with the fleet fuel standards.

They didn't discontinue DFM due to this failure it was discontinued due to no chips to activate the DFM the motor still has all the components in the motor for DFM it just won't engage due to no chip. 

Posted (edited)
2 hours ago, voided3 said:

Completely agree, but they'll probably never deactivate DFM on existing vehicles as that's tampering with emissions control systems.

 

 

What does DFM have to do with emissions? It is for fuel mileage improvements.

 

If this statement were true they would not be able to sell new trucks without the chip to run it as it is disabled and from my understanding will never be re-enabled on these trucks.

Edited by WeGone
Posted (edited)

I was reading online today that this guy was a GM mechanic an GM is now saying the lifter failure may be the cause of the auto/start stop system that when the motor stops oil is going back into the crank and on restart the oil has to pumped back up again for lubrication. Don't ask where I found it because I know ill never be able to find the page again, kind of make some since. Without the chip it also disables DFM along with start/stop. :dunno:

Edited by Silverado4x4
Posted
2 hours ago, Silverado4x4 said:

I was reading online today that this guy was a GM mechanic an GM is now saying the lifter failure may be the cause of the auto/start stop system that when the motor stops oil is going back into the crank and on restart the oil has to pumped back up again for lubrication. Don't ask where I found it because I know ill never be able to find the page again, kind of make some since. Without the chip it also disables DFM along with start/stop. :dunno:

Makes sense, losing oil pressure never is a good thing and I can't stand auto start/stop. I've always manually disabled auto start/stop on our truck from day one and the lifters still prematurely failed at 585 miles (though primarily due to manufacturing defect). Prior to 2019, the 5.3 and 6.2 didn't have auto start/stop, either, and that generation also runs into lifter failures after a few years of normal use.

 

We also have a Mini Countryman with auto start/stop and mercifully on that car when you turn it off, it stays off for good for every subsequent ignition cycle. It has a little 1.5 liter 3-cylinder turbo and I can only imagine what favors losing oil pressure at every red light does for the turbo, hence why I disable it on that car, too.

Posted

These lawsuits are a waist of peoples time and money... except the lawyers I guess...

 

GM knows how to manage these things by now 🤨 I imagine they'll soon start suing people, for suing them and win.

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