Batteries leak. Batteries are vented and the PCM controls charging so if it was overcharging there would likely be a code in the PCM along with a CEL for a circuit fault along with multiple modules shutting down due to an over voltage condition. Corrosion at the terminal is because the electrolyte is leaking past the post seal in the case. You can either maintain it by cleaning it regularly or replace the battery.

 

Thanks.
I didn't mention, the one cell next to the positive terminal was very low on water. All other cells were full. I cleaned up the terminal and applied NO-OXID. The corrosion occurred in the period between oil changes. Maybe six months. I normally would have checked it. Maybe I missed it on the last maintenance. It was well hidden under the cap.

 

Replaced the OEM batteries with AGMs. No terminal corrosion issues to date.

 

What AGM did you go with that give enough cranking power?

 

Mine is worse that yours. My truck sits a lot of the time, so I use a battery tender (high quality Deltran).

Anyway, mine got so bad that it corroded the hold-down bracket and I had to clean it, strip it and repaint it.

Something else worth mentioning is this summer my truck was used more than normal so I didn't have it on the charger and still got corrosion.

It's also currently corroding, which is a project for today...clean and inspect.

 

When this has happened to me it has been caused by a very small leak in the battery case. The poster who mentioned he had one cell which was consistently low makes me think that was also his problem. Mix a solution of baking soda and water. Slobber that around on the top of the battery. If it boils up vigorously then you likely have a leaker. A little bit of reaction is normal but a leaking battery will put on a real show when the acid hits baking soda.

 

Anyway to stop the leaking other than replacing?

 

Not that I'm aware of. But I'd be happy to be proven wrong.

 

What about grease around the post?

I bought a truck from an 85-year old man and he used to paint around his terminals after attaching to the posts.

That truck still has no corrosion issue to this day even though all my others (except for Optima YellowTops) do have corrosion since it seems to get sucked under the insulation of the cables.

I have not found a new battery prevents future corrosion issue.

 

This is becoming a real common problem with 2017 and newer trucks. The connectors on the end of the cable get eaten up by the battery acid ( you can argue about the source or reason) The problem becomes, that cables are just exactly the right length. So if the terminal connector needs to be replaced and you cut the cable back any, It will not reach the battery post. The new cable is $700 and was on indefinite nationwide backorder when I checked on it in July ( when mine went bad) If you have the Ford Dealership install the cable. The total bill is almost $2000. Because of the routing of the cable and the time involved in replacing it. I ended up cutting my cable back past the corrosion and Butt Splicing on an added 6" of cable so I could reach the terminal. Upon inspection, I found the other battery also was corroded and I repeated the process on it. My 2017 truck had about 75,000 on it when this happened. I've talked to several others and found it's a common problem. Take extra care to keep those terminal clean.

 

Solid advice! Thanks!!

 

It's funny how many stock batteries leak so much. My 15 had a leak but it wasn't around the terminal. You couldn't see where it was leaking from but it was eating the hold down bracket across the battery. They replaced it and battery. My 07 GT500 had a leaky battery and I caught the leak before to much damage. This is one thing I always do is watch the battery for corrosion. I have replaced my batteries with Motorcraft batteries and no more corrosion. Not sure what the difference is between the stock ones and the ones the dealer gets. I don't have any leaks and it's been 3 years now. I need to replace the one in my Crown Vic with my next oil change. It's starting to leak.

Everyone should lift the hood at least once a month.

 

Everyone should lift the hood at least once a month.

I had no idea there were drivers who didn’t open their engine hood at least once a week, let alone once a month except wives and daughters no insult intended to our lady gear heads / diesel heads Lol !

 

"Everyone should lift the hood at least once a month."
This statement should be taught to anyone that is applying for a drivers license!
Every time I do it is is a new adventure. I never know what I am going to find, leaking oil, coolant, Freon, battery acid, and the list goes on. Sometimes you even find things you have been missing, beer koozie's, wrenches, sockets, sometimes both, cell phones (most of the times with smashed screens, wondered why it took such a hard slam to latch the hood).

 

I'm a car guy and love to look at my motor. I don't know what that is but I think they are just the coolest things to0 see, I hate with a passion those plastic covers on the motors these days. It's a way for manufactures to hide the poor looking parts they put on motors. I like to see the mechanical workings. Nothing like lifting the hood and see a plastic cover. "nice looking cover you got there" There is one on my 12 SHO and it's the ugliest thing ever. It looks cool under there with all the piping and wires.

 

I used to have a lot of corrosion on my battery terminals, and it damaged the terminals and cables as well. So I replaced the cables with new Motorcraft cables, and put in AGM batteries. No problems anymore. With the AGMs it always starts and there is no corrosion so far.
ODYSSEY 65-PC1750T

https://www.amazon.com/dp/B00249GW9...=F-350 Super Duty|670&Year=2001|2001&ie=UTF8&vehicleId=1&vehicleType=automotive