Sponsored

New 2020 GT350 HEP engine failure

sox3

Well-Known Member
Joined
Jun 2, 2019
Threads
16
Messages
1,206
Reaction score
2,053
Location
Newark, Delaware
First Name
George
Vehicle(s)
2019 GT 350 Performance Blue

Stage_3

Well-Known Member
Joined
Jul 12, 2015
Threads
8
Messages
7,364
Reaction score
6,097
Location
MA
Vehicle(s)
2019 Roush Stage 3
Man, that sucks OP. Sorry to read.
Good luck going forward and keep us posted!
 

Sponsored

olaosunt

Well-Known Member
Joined
Jan 10, 2015
Threads
72
Messages
4,291
Reaction score
1,575
Location
Indiana
Vehicle(s)
Guard,base,M6,KB-2.DIB,auto,Hellion TT,2016 GT 350/Gen 3 Whipple ,2018 Mustang GT/Gen 5 Whipple
You aren't the resident expert? Lol sure had me fooled

When I did a Google search the most common causes are the timing chain or the valve spring breaking.
LOL , i am only an expert at blowing up shit !
 

stanglife

Well-Known Member
Joined
Jul 6, 2014
Threads
180
Messages
7,046
Reaction score
5,785
Location
FL
First Name
Jeff
Vehicle(s)
1993 Coyote Coupe
Ok. What would you hardly refer to it as then ? The bottom line is that it's no longer being made. I'm sure there are several reasons for that, I was just wondering aloud what those were. I don't own one, so I have no beef ...
To say they "killed it off" was suggesting they had to stop making it for some other reason other than the life of the car they said was the only car that would get it had run it's course. I call it normal.
 

stanglife

Well-Known Member
Joined
Jul 6, 2014
Threads
180
Messages
7,046
Reaction score
5,785
Location
FL
First Name
Jeff
Vehicle(s)
1993 Coyote Coupe
Some Ford apologists here have a habit of ad hominem attacks instead of rational reasoning. They are armchair psychologists who want to analyze your mood and judge your motives. We should simply ignore them.
You're accusing others of non rational reasoning? If refusing to making shit up is not rational....then I guess!
 

Super-Genius

Well-Known Member
Joined
Dec 10, 2020
Threads
2
Messages
151
Reaction score
206
Location
Austin Tx
First Name
Timothy
Vehicle(s)
2020 Oxford White Mustang GT
To say they "killed it off" was suggesting they had to stop making it for some other reason other than the life of the car they said was the only car that would get it had run it's course. I call it normal.
I'm not sure what you just said ... but ok, sure
 

stanglife

Well-Known Member
Joined
Jul 6, 2014
Threads
180
Messages
7,046
Reaction score
5,785
Location
FL
First Name
Jeff
Vehicle(s)
1993 Coyote Coupe
Autopsy pics:

GT350HEP4.webp


GT350HEP5.jpg


Perfectly normal for this to happen 24 days after you purchase your car brand new.

GT350HEP6.jpg


GT350HEP7.jpg


GT350HEP8.jpg


Some asked for the builder plate. Here it is. I'm not blaming the builder. It may as well be a faulty part.

GT350HEP9.webp
Good pics - nice they have it covered up some and are letting you check it out.

@honeybadger Check out the missing followers - wonder if they popped those out or they came out? I've thought a few times that a seized cam could cause the chain to break...honestly, the chains are so strong, I'm surprised they aren't the one thing still together and everything else shredded. If the cam seizes, especially on those big intake valves - could pop those followers and break the chain/opg.
Cams seize from oil starvation, typically....debris in the oil system or getting galled(sp) early on from lack of initial oiling. Built an 01 Cobra motor where the heads had been sitting for a while and a cam seized in about 20 seconds...in that case, the cam sprocket on that cam broke. I wonder if they'd be willing to put a wrench on that intake cam to see if it can move at all.
 

Sponsored

shogun32

Well-Known Member
Joined
Feb 8, 2019
Threads
92
Messages
16,223
Reaction score
14,020
Location
Northern VA
First Name
Matt
Vehicle(s)
'19 GT/PP, '23 GB Mach1, '12 Audi S5 (v8+6mt)
Vehicle Showcase
2
cam shafts have clearance so seizing is not really all that common. If they did in fact weld themselves to the journals that level of damage is very, very easy to see if you pop some of the cam caps. Surely a "helpful" technician could undo some "by accident". I agree Hi-vol chain is usually VERY strong stuff. If the cam stopped dead I would fully expect to see teeth sheared off the gears.

Is the entirety of the VCT range 'safe' for operation at all RPM ranges? Or are only certain combinations legal, such that illegal ones run a high risk of mechanical interference?
 
Last edited:

mk1spyder

Well-Known Member
Joined
Nov 20, 2020
Threads
2
Messages
101
Reaction score
67
Location
NC
First Name
Andrew
Vehicle(s)
2020 GT350R TT005
Either the chains or the tensioners are the issue. HOPEFULLY it was just a part quality issue and maybe some day someone will make upgraded chains for these cars. Like on motorcycles there are a variety of chain upgrades, fundamentally these are the exact same. The stock chains are TINY in my opinion but what do I know.

Side note, my car they didn't take anything apart or even touch the top of the engine bay much, they just dropped the whole subframe out and slapped another engine in. I dropped it off on thanksgiving day (thurs) they had a new engine sitting next to the car the following Monday which is crazy because every other part in their catalog is on backorder lol.
 

lenFeb

Well-Known Member
Joined
Dec 31, 2019
Threads
30
Messages
956
Reaction score
847
Location
USofA
First Name
Len
Vehicle(s)
2019 Shelby GT350 #K0110
Last edited:

shogun32

Well-Known Member
Joined
Feb 8, 2019
Threads
92
Messages
16,223
Reaction score
14,020
Location
Northern VA
First Name
Matt
Vehicle(s)
'19 GT/PP, '23 GB Mach1, '12 Audi S5 (v8+6mt)
Vehicle Showcase
2
The below are seven instances with similar failed engines symptoms for 2020 GT350 that I searched on this forum.
let's assume that all 7 are the entirety of the observation pool. Of the M6G membership let's say maybe 200 persons are 2020 GT350 owners. Is that fair?

That's a 3.5% failure rate. If Coyote3 were failing at just 0.35% (1/10 as frequent) and assuming 65% of M6g forum members drive GT we'd have 0.0035 * 30,000 = 105 threads about infant mortality Coyote3 "new" off the show room floor. But that includes all 2015-2020 cars so let's just arbitrarily divide by 6 to make it represent a single MY. That would be 17 cases among just forum members. Have there even been 5 such threads? Or even 20 threads if we look at all years 2015-current?

Hell the units of Coyote3 on F150 positively dwarf Mustang so you'd think there would be a huge cacophony of pissed off truck buyers swarming those forums.

Yes self-selection bias is a real thing but even if this napkin math is off it still suggests Ford has a serious problem with their Voodoo engines be it design, manufacturing, or QC that can't be papered over by "everyone has shitty engines".
 
Last edited:

mk1spyder

Well-Known Member
Joined
Nov 20, 2020
Threads
2
Messages
101
Reaction score
67
Location
NC
First Name
Andrew
Vehicle(s)
2020 GT350R TT005
The below are seven instances with similar failed engines symptoms for 2020 GT350 that I searched on this forum.
Say that these are not all reported, still I don't think there are "many" failures for this engine. Moreover, same people posting here also posting on FB which blow out this issue from proportion. That being said, I'll be very upset if my failed. Sorry OP for your trouble.

1. https://www.mustang6g.com/forums/threads/2020-shelby-gt350-engine-failure.133081/
2. https://www.mustang6g.com/forums/th...-booboo-engine-replacement-experience.137204/
3. https://www.mustang6g.com/forums/threads/another-2020-gt350-engine-failure.137780/
4. https://www.mustang6g.com/forums/threads/my-2020-gt-350-engine-blew-today.138273/#post-2840377
5. https://www.mustang6g.com/forums/threads/new-2020-gt350-hep-engine-failure.152495/
6. https://www.mustang6g.com/forums/threads/2020-shelby-gt350-engine-replacement-dropped-valve.152472/
7. https://www.mustang6g.com/forums/threads/help-on-new-engine-or-buyback.149426/
Your search is missing some, mine for example. If you consider how many 2020 were made and that they are all the same root cause, and figure maybe 20-30% get on the forums and talk about it. Its a pretty widespread issue amongst the 2020 cars.
Sponsored

 
 








Top