If Trump would get rid of the EPA and do away with the stupid CAFÈ then maybe the manufacturers could build a motor that would last. We did not have these issues until auto start stop and cylinder deactivation came to be.
-
We are late but the Chevy ZR2 Photo of the Month Contest is live! Please check it out at the following URL: Chevy ZR2 Photo of the Month Contest - January 2025 (You can dismiss this message by clicking the X in the top right hand corner of this notice.)
GM can't build 6.2's fast enough to meet demand for new and broken ones
- Thread starter Waterdog
- Start date
Because he has a white truck. That’s it. Lol
My thing is, other manufacturers have the same thing. You hear it at stop lights. Everyone’s vehicle turning back on, all these other car company’s having the same issues?
As much as I want to buy into the disable DFM and problems are solved I cannot.
The reality is GM buys batches of lifters in the hundreds of thousands so a “bad run” will screw up tens of thousands of units.
*Knock on wood here*
I drove an AFM 5.3 with religious oil change intervals for 150k and this 6.2 for 25k thus far. Not a tick let alone side of the road.
Some of it is luck of the draw but let’s be real here. Turning off DFM will not save you if the spring breaks inside the lifter and it collapses. That’s a QC issue from the supplier.
The reality is GM buys batches of lifters in the hundreds of thousands so a “bad run” will screw up tens of thousands of units.
*Knock on wood here*
I drove an AFM 5.3 with religious oil change intervals for 150k and this 6.2 for 25k thus far. Not a tick let alone side of the road.
Some of it is luck of the draw but let’s be real here. Turning off DFM will not save you if the spring breaks inside the lifter and it collapses. That’s a QC issue from the supplier.
SGRACING
Well-known member
As a professional engineer and custom motor builder your way off the mark.. No pun intended
And not trying to disrespect your opinion ,but it is just an opinion. Some of your statements are facts. And the rest speculative. Dynamic Fuel Management is a novel idea based on regulatory mandate. All manufacturers are struggling with ideas. It just so happens that the current set of dynamic are all known.
This forum is to general for me to explain to you all the variables. So I'm gonna say GM know and is willing to allow said device development to shut off some or all of the variables. They clearly know the savings.
To conclude Range DFM delete is a positive step in saving them money.
I get that most don't understand why .
Any time a system tries to control oil pressure to regulate efficiency is looking for connective failures! Simply put that's why shit happens!
And not trying to disrespect your opinion ,but it is just an opinion. Some of your statements are facts. And the rest speculative. Dynamic Fuel Management is a novel idea based on regulatory mandate. All manufacturers are struggling with ideas. It just so happens that the current set of dynamic are all known.
This forum is to general for me to explain to you all the variables. So I'm gonna say GM know and is willing to allow said device development to shut off some or all of the variables. They clearly know the savings.
To conclude Range DFM delete is a positive step in saving them money.
I get that most don't understand why .
Any time a system tries to control oil pressure to regulate efficiency is looking for connective failures! Simply put that's why shit happens!
I think both are correct statements given the proper context. AFM/DFM is subject to both short term and long term effects related to design and maintenence. As Wutang stated, I've run two high mileage AFM motors with excellent maintenence and never a problem. Most issues were caused by uneven wear on the cam due to the four cam/lifters that were not shut off during deactivation. DFM is a new design rotating amongst all cylinders and subject to failure from incorrect machining, improper oiling, and bad lifters.
So it's unlikely you'd see catastrophic failure in the AFM systems, but long term wear issues, which better maintainece practices can increase life. DFM has a lot more variables and is generally caused by catastrophic failure so they go to hell much quicker. Even with better maintainece and the DFM module, it may not be enough to prevent failure if the parts are bad.
So it's unlikely you'd see catastrophic failure in the AFM systems, but long term wear issues, which better maintainece practices can increase life. DFM has a lot more variables and is generally caused by catastrophic failure so they go to hell much quicker. Even with better maintainece and the DFM module, it may not be enough to prevent failure if the parts are bad.
Last edited:
As luck would have it, Dave's Auto just did an autopsy on a 6.2L motor with four miles on it!
I guess GM didn't want it back cause they already have thousands sitting there......saves on return shipping.....LMFAO.
Actually, I think it's a failed reman hence the reason it's a 23 with 4 miles, the pistons look used, and there's a heat tab on the block which is used for reman motors. There are comments like that on the video.
I guess GM didn't want it back cause they already have thousands sitting there......saves on return shipping.....LMFAO.
Actually, I think it's a failed reman hence the reason it's a 23 with 4 miles, the pistons look used, and there's a heat tab on the block which is used for reman motors. There are comments like that on the video.
Last edited:
So I've been entertaining purchasing a ZR2 but am hesitating pulling the trigger after reading these adventures. I'm a mechanical engineering and very curious about the cycle and sequence of events with this DFM. I'm fastidious about maintenance but if failure is a foregone conclusion down to not if but when then I'm happy to wait to see if this gets sorted out later in 25' or 26'. With the DFM range unit can you elaborate on the circuit? I.e. if it keeps all cylinders running is there any time when the oil pump shuts down or reduces oil pressure to catastrophic levels? Thanks in advance.....B
andrec10
Well-known member
Change your oil every 5k miles and move along. Even my dealer recommends this!
SGRACING
Well-known member
Yes I can elaborate just a little
1st yes oil pressure is no longer regulated with the Delete
2nd all lifters are regulated full pressure , zero collapse!
3rd motor Valcum is now stable , reducing none paracidic drag on rods and crankshaft
This process is the most important aspect to the delete process! And without delete this is were all things go south. Bearing failer and fatigue.
4th Fuel management is still active and on some models it can and will equate to zero combustion pressure at low rpm. Hence no power..! This doesn't effect the throttle demand or acceleration!
Hope this helps!
Remember oil change cycles should be between 3 and 5k miles for optimum life on
Low Paracidic drag oil "0w-20w"
The redesign lifter will benefit from the oil control issue and in my opinion is not the current problem.
Past issues of the lifter was manufacturing flaws , material flaws ECT..
Not a current issue!
Thanks so much for the explanation, yes I religiously change my oil in my vehicles every 3000 miles without fail. I have a 2004 GMC 1500 Sierra with a 5.3 that has 320,000 miles on it and still going strong.
SGRACING
Well-known member
Lol, I hear ya!!
But I am an Engineer for an aerospace firm
I write book for as9100 process.. For over 45 years!
That's my real job ..
But I have a pro motor shop and Design and build custom power for all aspects for over 30 years . I get to enjoy my passion...
Get one now and see how it goes! You can always get another one later. I see them showing discounts of $8k. Tell your salesman you want -$12k to cover the cost of an extended warranty for the risk.
The optimum change interval is 3333.33 miles, with the 3rd in the sequence should be 3333.4 so you do three changes per 10k miles. All changes should be self performed and you should send in an oil sample every every 6666.66 miles or 6666.67 on the forth change in the sequence. All changes should use Mobil 1 0W20 oil and a Delco PF63 filter from Walmart at a cost of $57.27 per change for a total 10k cost of $171.81.
You can see my oil change threads with filter dissections and oil analysis results. Also follow me on X for more engineering tips and life hacks!
SGRACING
Well-known member
Old habits........as far as I know, the only oil we used at the farm simce the 60s was Mobil (probably Standard Oil before that), grease too. In more recent years, we've run Rotella in some of the diesel equipment, and I use it in my personal rigs too.Very good Axe.....!
The wally world connection is spot on!
I feel bad for ya on the oil choice but to each there own...
Also I don't always buy at Walmart, I ask O'Reilly to match price and they get me close. I like to have them on the corner and I have to dump the oil there an puck.up some other goods too.
SGRACING
Well-known member
Silverado ZR2 Photos
Silverado ZR2 Photos
Most Member Reactions
-
746 -
394 -
270 -
231 -
207 -
A
159
-
140 -
140 -
138 -
132 -
131 -
127 -
125 -
122 -
114
