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GT350 OEM ECU Software Update - Piston Slap Reduction

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The service guy at the counter looked at me funny but once I got to the service manager, he knew exactly what I was after.
It's almost like you have to know the secret wink & nod to get past the guy at the door.:cool:
Curious to see if you have similar results. Standing by......
 
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1,243
In the V6L
So, I've been running this update for three months now, and aside from the improved piston slap, the biggest change is the way low-end torque works. It's just so much more civilized. I didn't used to feel comfortable in 6th below about 65MPH, and now it's fine all the way down into the 50's. You're not going to win any races at 1600RPM, but when you're in a 50MPH zone, locked on cruise control, on the highway where the WA State Patrol trains cadets to use radar, it's fine. It doesn't feel like it's on the brink of stumbling, which it used to.

I also found a backup copy of the screen shot that has the revised software part number:

GT350 ECU Update Screen Shot - 2019 03 21.png
 
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I need to get this done while my car's down. Its pretty dysmal under 3k.

Does yours surge at all when cold? Mine doesn't seem to burn measurable oil whatsoever, but when its not fully warmed up, there's a bit of light throttle surge.
No surging, cold or otherwise, now or in the past before the update.
 

50Deep

Jockin' GT350's
837
835
Sacramento
Just had this done recently. The predicate issue for this to be installed was the issue with the exhaust flaps not properly opening or closing and causing an issue with the selector modes. Be sure you mention that you are looking to have this issue fixed and not just a PCM update for piston slap. In order for Ford to cover the work it has to be related to the issue the update was made for.

Your mileage may vary, but this was the verbiage that needed to be used in order for the dealer to get reimbursed.

Overall the car feels better down low. Some of it may be placebo, but some of it is definitely real. Piston slap appears to be reduced as well.
 
I live in Austria (Europe) and just had this done. To generate the drive mode fault, pull relay 59 in the fuse box up front. The relay controls the exhaust valves. Pull the relay and take a drive. I did this multiple times over 3-4 days. When they hook up IDS it will show all the faults. They will do the update then. The PCM software version on my car was FR3A-12A650-FFA and FR3A-12A650-FFB (as posted above) after the update. Did it with no questions asked. Their IDS was able to get the software even here in Europe. Took 15 min tops. Here is a picture of the fuse box on the passenger side in the engine compartment. It's relay 59
Fuse - Relay Box.jpg
 
225
312
Exp. Type
HPDE
Exp. Level
5-10 Years
Virginia
I took a copy of the service bulletin to the dealer today and explained I had some intermittent exhaust mode not available issues. I also told them I was hearing some tapping sounds on passenger side most prominent from wheel well when oil was above 170 degrees. Upon there initial inspection the tech told me if it's not exhaust or something else simple Ford would likely just replace engine...I wasn't prepared for it to get that serious as it seem pretty minor. Due to the hurricane possibly headed our way I told him I'd rather the car sit in my garage rather than in a parking lot if you're not ready to fully diagnose. He agreed but, did accomplish the reflash. The car definitely feels better with the updated software, as for the tapping its still there.

Hope it's something simple...more to come.
 
Some of you might know that I have a genuine Ford VCM II OBD connector, the one the dealerships use. Once or twice a year, I get a short-term Motorcraft IDS software license so I can hook up to the car and do the diff oil service and otherwise check to see that the electronics are all happy. This time, when I got the system all loaded up and connected, I also updated the ECU software to the latest version. I didn't expect much difference; I was curious, more than anything.

Well, I have to say "It's different". Really different. Piston slap on my engine has always been annoying and loud. It's pretty much gone now - it's there if you listen for it, but it's not as obtrusive as it used to be by a long ways. The engine runs smoother too. Nothing major, but the flat spots in the torque curve are gone. It's a different feel from what it was. There seems to be a bit more torque lower down, but it could be an illusion. Anyway, I like it.

So, for those of you who want to reduce piston slap, Ford has released a new software version for at least the 2016's that reduces it. Getting it installed is another matter. Unless you invest in a lot of expensive tools, it's not a DIY job. Independent shops can do it, and of course a dealer can, although the cost of installation won't be covered by warranty. And before anyone asks, it's way beyond anything that Forscan can do.

Just bought my 2016 GT350 two months ago. The piston slap is very audible. Very frustrating. I took the car into Ford, and they referred to the bulletin that says the noise is normal and did not offer any resolution at all. I asked him if there was anything I could have done (under warranty or otherwise), and he said nope. Should I just try another dealer and ask about this remedy?
 
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The job takes about 10 minutes, although it could be longer if there are other modules that need updates first. In any case, after I'd done this update myself, I was at the dealer for some parts so I asked the service dept about paying to get it done and they said if I had come in and was willing to pay, they'd have been happy to do it and an hour should cover it.
 
I was originally quoted 1 hr of shop time but in the end, they didn't charge me anything.
Watching from the customer area window was somewhat entertaining. Other techs were stopping to chat with the tech working on the car.
I'm pretty sure the flash didn't require any blips of the throttle but there was more than a few.....Res delete sounds great indoors. Even better than driving under an overpass. ;)
 

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