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What did you do to your GT350 today?

dpAtlanta

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Replaced my original battery with a date of manufacture May 31, 2016. Almost 8 years.
I changed my battery with an OEM Ford battery early last month... it took weeks for the car to re-learn how to behave.

The idle was stumbling and rough until the MAS and its partners tried to remember their marching orders.

When I filled the tank historically, I would get a fuel range of 220 - 225 miles till empty. With the new battery and the confused electronics, I was told by the electronic wizards that I now have 376 miles till empty. I went from 14 mpg to 27 mpg.

Not believing the fuel range or the fuel gauge level, I switched to noting the odometer, and refilling every 100 miles. It took about 7 - 8 refills before the fuel issue was getting back to normal.

If this is normal with a battery change, I am surprised I have not seen any threads discussing this. (I did not do a search)
 
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moby4dick

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I changed my battery with an OEM Ford battery early last month... it took weeks for the car to re-learn how to behave.

The idle was stumbling and rough until the MAS and its partners tried to remember their marching orders.

When I filled the tank historically, I would get a fuel range of 220 - 225 miles till empty. With the new battery and the confused electronics, I was told by the electronic wizards that I now have 376 miles till empty. I went from 14 mpg to 27 mpg.

Not believing the fuel range or the fuel gauge level, I switched to noting the odometer, and refilling every 100 miles. It took about 7 - 8 refills before the fuel issue was getting back to normal.

If this is normal with a battery change, I am surprised I have not seen any threads discussing this. (I did not do a search)
There’s a thread somewhere about a new battery reset procedure, which can be done in Forscan, or you bring it to a dealer. Not sure if there’s a magic button press option.
 

Nfs1000f

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I changed my battery with an OEM Ford battery early last month... it took weeks for the car to re-learn how to behave.

The idle was stumbling and rough until the MAS and its partners tried to remember their marching orders.

When I filled the tank historically, I would get a fuel range of 220 - 225 miles till empty. With the new battery and the confused electronics, I was told by the electronic wizards that I now have 376 miles till empty. I went from 14 mpg to 27 mpg.

Not believing the fuel range or the fuel gauge level, I switched to noting the odometer, and refilling every 100 miles. It took about 7 - 8 refills before the fuel issue was getting back to normal.

If this is normal with a battery change, I am surprised I have not seen any threads discussing this. (I did not do a search)
I changed the battery out myself at the dealer, so my car sat without power for just a few minutes. Only drove a couple miles, but everything seemed fine. Ran normal and everything worked. I’ll find out if I have any issues in my drive later this week.
 

galaxy

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The FatHouse is a nice example a
There’s a thread somewhere about a new battery reset procedure, which can be done in Forscan, or you bring it to a dealer. Not sure if there’s a magic button press option.

There is an in car cheat code, yes. Does the same BMS reset as forscan. You don't need that or a dealer. I don't have it handy, but it's floating around in a few threads around here.
 

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dpAtlanta

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I changed the battery out myself at the dealer, so my car sat without power for just a few minutes.
I bought the battery at the dealer, and swapped it at home.
There was no power to the car for about 20 - 30 minutes.
I was in no hurry since I didn't know time unplugged may equal electrical mayhem to follow.

I wonder if connecting a trickle charger to the +/- terminals during battery change would have prevented the mayhem?

It's now back to normal, so I'll worry about it in 5 years.
 

tj@steeda

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I replaced mine with the Steeda brand. It's very well built and I don't have to worry about an external tube leaking like on the other after market brands. I did my first track day with it and it was rock solid. In my opinion the oem should never have been plastic..
Mine is also a 2019 and the plastic unit didn't look pretty.
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20240229_211107513_iOS.jpg
Great choice :)
 

galaxy

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Might check out this thread and these posts.
Those threads are huge, and I’m quite sure I read them when I got my last battery. Were you trying to highlight something or make a point (sincerely not being a smart ass; curious)?
 

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GT Pony

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Those threads are huge, and I’m quite sure I read them when I got my last battery. Were you trying to highlight something or make a point (sincerely not being a smart ass; curious)?
Those two links go to posts that might be useful - yes, I put those specific links there so people don't have to read the whole thread.

In the first post link (with the YT video), it sounds like the BMS takes care of itself if you don't disturb the car whatsoever for 8 or more hours. Fully charge the battery and don't disturb the car for 8+ hours.

Also, notice from the Service Manual info shown in link #1, that when charging the battery with a charger, you should put the negative cable of the charger on a chassis ground, not directly on the negative terminal of the battery.
 
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young at heart

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I bought the battery at the dealer, and swapped it at home.
There was no power to the car for about 20 - 30 minutes.
I was in no hurry since I didn't know time unplugged may equal electrical mayhem to follow.

I wonder if connecting a trickle charger to the +/- terminals during battery change would have prevented the mayhem?

It's now back to normal, so I'll worry about it in 5 years.
Yeah, apparently something along those lines works and must be an insider’s trade secret. When I had the original battery replaced last year in my ‘20 GT I asked the guys if I’d have a relearning issue. They said not to worry, they hooked up to another power source before disconnecting the outgoing battery. It was one of those Quick Lane places that was part of the selling dealership so I figured they knew what they were doing.
 
 




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