Blown engine

[CB34]

Totally different engines assembled in different plants. No relation whatsoever.

Different plants but I suspect some shenanigans have been going on with either sharing parts or using the same suppliers to make similar parts with the same defects for both engines.

 

[blkout]

Different plants but I suspect some shenanigans have been going on with either sharing parts or using the same suppliers to make similar parts with the same defects for both engines.

Naa. Not only different plants but different parts completely.

 

[NorCal Blackwing]

Naa. Not only different plants but different parts completely.

Nuh uh! Every piece of the Blackwing LT4 engine is designed, machined and assembled by GM PhDs by hand while wearing white lab coats. Sorry I could not resist a tiny bit of sarcasm.

Appreciating the crankshaft is a different part and that the engines are not the same, the failure modes of the LT4 on the 'blown motor registry' do seem an awful lot like the failure modes of the L87 - i.e. lifters, or bottom end failure related to the crankshaft and/or bearings.

I guess there are only so many ways a pushrod V8 can fail, but it wouldn't surprise me if the same supplier made the same mistake (or cut the same corners) with two completely different crankshafts. Or GM wrote a specification that caused two different suppliers to provide something that fails in the same way.

I would love to be wrong. If I'm not I really hope GM doesn't try to shaft those of us that keep these cars out of warranty. That's the only reason I created the 'blown motor registry', so it's minimally less possible to sweep it under the rug.

I'm still hoping I keep this car forever, nothing I'd rather drive!

 

[Jakemey]

Here we go , 2022 Ct5v bw three months into ownership been left of the side of the road twice and now have a blown up motor at 8500 miles (sold my m3 comp for it) first issues was the alternator seizing and making one of my belts snap, then it just randomly died while i was driving on the highway, and got the call that the bottom end was blown and they need to replace the whole engine lol. I have so many questions like how does this affect the value of my car , can Cadillac or GM do anything to help with the troubles this has caused? I bought it used in fl with 5500 miles on it so there is no lemon law or anything , I’m stuck , obviously everything I’d covered under warranty but let’s say i want to get out of it am i going to be buried in this car now ?
Hopefully someone can help me here

UPDATE : they said they engine is already replaced and ready for pick up , they had one in stock apparently and put it in today in going to pick it up tomorrow we’ll see

 

[NorCal Blackwing]

UPDATE : they said they engine is already replaced and ready for pick up , they had one in stock apparently and put it in today in going to pick it up tomorrow we’ll see

Dude that has got to be some kind of record. Thanks for the update. That makes me think GM is more on top of this thing.

 

[blkout]

Nuh uh! Every piece of the Blackwing LT4 engine is designed, machined and assembled by GM PhDs by hand while wearing white lab coats. Sorry I could not resist a tiny bit of sarcasm.

Appreciating the crankshaft is a different part and that the engines are not the same, the failure modes of the LT4 on the 'blown motor registry' do seem an awful lot like the failure modes of the L87 - i.e. lifters, or bottom end failure related to the crankshaft and/or bearings.

I guess there are only so many ways a pushrod V8 can fail, but it wouldn't surprise me if the same supplier made the same mistake (or cut the same corners) with two completely different crankshafts. Or GM wrote a specification that caused two different suppliers to provide something that fails in the same way.

I would love to be wrong. If I'm not I really hope GM doesn't try to shaft those of us that keep these cars out of warranty. That's the only reason I created the 'blown motor registry', so it's minimally less possible to sweep it under the rug.

I'm still hoping I keep this car forever, nothing I'd rather drive!

Has the blown motor registry grown beyond 16? Last time I checked that thread, it was showing 16 engines. That's a VERY small number given that there are roughly 6,000 or more of these cars built.

 

[rubberduck]

I guess there are only so many ways a pushrod V8 can fail, but it wouldn't surprise me if the same supplier made the same mistake (or cut the same corners) with two completely different crankshafts. Or GM wrote a specification that caused two different suppliers to provide something that fails in the same way.

Don’t blame it on the engineers. GM has been designing these type of parts for 100+ years, unlikely they suddenly forgot how to make them. My bet is on the fucking bean counters. They’re very good at taking a great design and turning it into a pile of shit.

 

[hawk02]

I traded a 2017 Camaro ZL1 M6 that I owned for almost seven years for my 2023 5BW. The first thing I noticed about the BW was that it had a bit more giddy-up than the ZL1—more than could be explained by just 18 extra horsepower. I’ve seen reports that timing can be in the neighborhood of 30 degrees at redline on these cars, which seems like an awful lot for forced induction. My theory is that the engine running in closed loop, thanks to the widebands, has given GM engineers more confidence in fueling. As a result, the ECM calibration is more aggressive when it comes to timing. I wonder if some engines just can't handle that much timing. I could be blowing smoke out my ass, but that’s my story and I’m sticking to it.

 

[blkout]

I traded a 2017 Camaro ZL1 M6 that I owned for almost seven years for my 2023 5BW. The first thing I noticed about the BW was that it had a bit more giddy-up than the ZL1—more than could be explained by just 18 extra horsepower. I’ve seen reports that timing can be in the neighborhood of 30 degrees at redline on these cars, which seems like an awful lot for forced induction. My theory is that the engine running in closed loop, thanks to the widebands, has given GM engineers more confidence in fueling. As a result, the ECM calibration is more aggressive when it comes to timing. I wonder if some engines just can't handle that much timing. I could be blowing smoke out my ass, but that’s my story and I’m sticking to it.

I have seen up to 32 degrees of timing in some dyno tests on Youtube. I agree with your assessment this could be a potential cause for these failures. The tuning is VERY aggressive as stated by top tuners. These cars do have much better throttle response than the ZL1 and I agree that it seems unlikely it's just because of the 18 extra HP. It must be the additional timing since that does increase throttle response or possible the throttle map is more aggressive like those aftermarket throttle controllers.

I have a 2024 CT5BW model and my wife has a 2025 CT5BW, I have driven both back-to-back many times and her 2025 feels even more responsive than my 2024 even though there's no documented changes in engine performance.

 

[Todd]

I traded a 2017 Camaro ZL1 M6 that I owned for almost seven years for my 2023 5BW. The first thing I noticed about the BW was that it had a bit more giddy-up than the ZL1—more than could be explained by just 18 extra horsepower. I’ve seen reports that timing can be in the neighborhood of 30 degrees at redline on these cars, which seems like an awful lot for forced induction. My theory is that the engine running in closed loop, thanks to the widebands, has given GM engineers more confidence in fueling. As a result, the ECM calibration is more aggressive when it comes to timing. I wonder if some engines just can't handle that much timing. I could be blowing smoke out my ass, but that’s my story and I’m sticking to it.

I've wondered if the engine cooling capacity is the variable that allows the LT4 to come in different power outputs. Taller radiator on the 5BW vs ZL1 allows for more power (via timing), and even taller radiator on the Escalade V allows for yet more power? 650-> 668-> 682.

 

[blkout]

I've wondered if the engine cooling capacity is the variable that allows the LT4 to come in different power outputs. Taller radiator on the 5BW vs ZL1 allows for more power (via timing), and even taller radiator on the Escalade V allows for yet more power? 650-> 668-> 682.

There's no difference in intercooler brick size on all LT4s, Z06, ZL1, or Blackwing, the only difference between them is the lids. While the taller lid on the Blackwing does help very slightly with airflow it was really only a restriction on the 2015-2016 Z06. I believe the timing increases are coming from the Global B tuning using wideband 02 sensors that can make adjustments quicker.

The Escalade V makes more power because it comes with a 2.65L supercharger and weighs 6200lbs.

 

[Todd]

There's no difference in intercooler brick size on all LT4s, Z06, ZL1, or Blackwing, the only difference between them is the lids. While the taller lid on the Blackwing does help very slightly with airflow it was really only a restriction on the 2015-2016 Z06. I believe the timing increases are coming from the Global B tuning using wideband 02 sensors that can make adjustments quicker.

The Escalade V makes more power because it comes with a 2.65L supercharger and weighs 6200lbs.

Not sure where I referred to the intercooler brick. I said engine cooling. Specifically radiator.

Thermal reserve of the entire engine cooling package plays a role in tuning.

 

[blkout]

Not sure where I referred to the intercooler brick. I said engine cooling. Specifically radiator.

Thermal reserve of the entire engine cooling package plays a role in tuning.

The cooling capacity in these cars only needs to be good enough to keep them at the desired temp. To my knowledge the ZL1 has better cooling than the Blackwing anyway so there goes that theory. What does matter is IAT temps which the blower intercooler bricks have control over and the cooling capacity of the intercooler loop. The timing of the vehicle is adjusted based on IATs which is the temp of the air entering the engine through the blower. That's what I thought you were referring to when you said radiators since the actual engine cooling radiator has no impact on timing as long as the radiator an maintain adequate temps, ie...not overheating. The ECM does adjust timing based on ECT (engine coolant temp) but my point is that if a ZL1 is able to maintain 200F ECT for example and a Blackwing is also able to maintain a 200F ECT, then the amount of timing pulled at that temp is going to be the same. I see where you're going with this but I don't think the engine cooling capacity is different enough between the ZL1 and the Blackwing to make any significant adjustments to timing.

 

[Jakemey]

UPDATE: picked up the car today , drives fine , apparently they had a engine replacement in stock, but suprised it doesn’t come with any additional warranty , also from what it sounded like they just put a 6.2 in it , and put the super charger back on , is there not a specific engine for it or anything like that ? It’s just like any other 6.2? And he said break in is 500 “just drive it normal then you can rip after 500 miles “ no oil change or anything needed ,?!? Is this true someone help me lol

 

[Argent86]

Congrats!
owners manual says rip after 1500 (track rip) but if you got the go-ahead then I may as well too I'm at 500.

 

[vagabond]

UPDATE: picked up the car today , drives fine , apparently they had a engine replacement in stock, but suprised it doesn’t come with any additional warranty , also from what it sounded like they just put a 6.2 in it , and put the super charger back on , is there not a specific engine for it or anything like that ? It’s just like any other 6.2? And he said break in is 500 “just drive it normal then you can rip after 500 miles “ no oil change or anything needed ,?!? Is this true someone help me lol

Not just like any other GM 6.2L engine, no, different internals and a few other things. The replacement parts need to be specific LT4 equipment..

 

[blkout]

UPDATE: picked up the car today , drives fine , apparently they had a engine replacement in stock, but suprised it doesn’t come with any additional warranty , also from what it sounded like they just put a 6.2 in it , and put the super charger back on , is there not a specific engine for it or anything like that ? It’s just like any other 6.2? And he said break in is 500 “just drive it normal then you can rip after 500 miles “ no oil change or anything needed ,?!? Is this true someone help me lol

There was no need to replace every component of the engine. They likely replaced the long block which is where the failure was. Keeps cost down that way.

 

[RDATLTE]

UPDATE: picked up the car today , drives fine , apparently they had a engine replacement in stock, but suprised it doesn’t come with any additional warranty , also from what it sounded like they just put a 6.2 in it , and put the super charger back on , is there not a specific engine for it or anything like that ? It’s just like any other 6.2? And he said break in is 500 “just drive it normal then you can rip after 500 miles “ no oil change or anything needed ,?!? Is this true someone help me lol

You need to get a (the) part number(s) of what they replaced. The LT4 is not just any old 6.2. Seems doubtful that they'd have an LT4 just sitting there.

 

[shbox]

Change oil early (500-1000 miles). Break-in bits need to be flushed out.

 

[RDATLTE]

There was no need to replace every component of the engine. They likely replaced the long block which is where the failure was. Keeps cost down that way.

True but, the LT4 long block is very specific.