Hey everyone.I need to clean corrosion on the battery terminals on my 05. I'm having problem w/ finding the right socket/wrench size that fits that nut. It's small w/ the small bolt which looks to me to be 1/8". Anyone know the size of that nut? I can fit a 11/32 over it but it won't catch. 5/16 and 8mm is too small. It's got so much crud that I can't really tell if it's a nut at all. Really appreciate the help.Thanks,Eugene

It isn't just the regular 1/2 or 7/16" nut? I can't imagine it being that small. If it is the big bolt that tightens the terminal then an 1/8" nut sounds pretty unreal for that application. The threads for the bolt come out pretty far, maybe they look like a nut since they are corroded? Maybe it uses a fancy terminal that I am not thinking of.

ISX.No it's not a 1/2" like the positive terminal or 7/16. My 11/32 fits over it but it wont grab. I was very surprised it's that small. I should of taken a picture. I'll do that tomorrow. Now I kinda wonder if the PO replaced it but both negative connector are the same. Strange.Eugene

mix baking soda with water let it soak and clean them first.Go buy some new bolts at the part store. Remove old ones with channel lock type pliars.Make sure you don't break the poles on the batteries. Hold both side of the bolt as you loosen them.Keep them clean in the future with baking soda mixed with water.add about a 1/4 cup of soda to half quart of water should be plenty

I did try to to turn the nut w/ channel lock but it won't budge. I didn't want to mess up that nut yet. I'll do the baking soda/water and clean it out first. Thank you both for the help.Eugene

If you can get a pic of it, maybe someone will be able to recognize what your dealing with and be able to help you.

At this point I would take and remove the battery lead from the battery. Using a hacksaw I would cut the bolt out of the terminal though the gap in the lead. Now you can replace the battery terminal bolt. As for keeping the corrosion free is simple I use good ol' engine oil. I take my oil can and give a small oil to each terminal and wipe around. Then very carefully squeeze a few pumps on the tie down bolts and let it run to the bottom. Here is my terminal after 9 years with my factory batteries yet... Take notice the hold down bolts at factory fresh and not all ate up and corroded.

At this point I would take and remove the battery lead from the battery. Using a hacksaw I would cut the bolt out of the terminal though the gap in the lead. Now you can replace the battery terminal bolt.

As for keeping the corrosion free is simple I use good ol' engine oil. I take my oil can and give a small oil to each terminal and wipe around. Then very carefully squeeze a few pumps on the tie down bolts and let it run to the bottom.

I think that's want I'm going to do. There is just not a way to take that nut out. Here is few pictures of it.

Eugene

Looks the same as Mike's only with the threads all corroded down so they smaller. Did you try vise-grips?

Yes, I did but I didn't force it. I didn't want to round out that nut. It's been raining all morning so I haven't messed with it. I'm pretty sure if I force it with a vice grip, it's going to break off. Do you think that corrosion eroded that bolt down to that size?

Yes, I did but I didn't force it. I didn't want to round out that nut. It's been raining all morning so I haven't messed with it. I'm pretty sure if I force it with a vice grip, it's going to break off. Do you think that corrosion eroded that bolt down to that size?

Well the nut looks the same size as stock (I think they are 7/16") and the square on the other end looks the same as stock. So I think it is all the same that was on it OEM. I don't know why the bolt would corrode that bad. I wonder if the bolts are zinc plated so it has a sacrificial anode seeing as how bolts are much easier to replace and cheaper than a terminal that has all those wires fitted into it. That battery must have been leaking around the terminal pretty good or just out of the vent and got directed to that terminal. When you get it all off, you might get a felt washer to put over the terminal just in case it is the culprit that is leaking. I've actually heard of a lot of people having good luck with vasoline, but just as many have the same luck by just checking their oil and letting the dipstick drip on the terminals.

Another old trick I'll place here that works!

WARNING! Don't do this on the battery.

With a propane torch heat the bolt up carefully so not to melt the lead. Get it as hot as possible and then dip it in cold water. What occurs is the metal expands as you dip in ice cold water the exterior metal contracts rapid and usual enough to loosen the fastener.

I done this trick on older metal battery hold downs and easily twist the nuts right off with your fingers...

But in your case with the lead terimnal you got to be careful...

I still say clean them up with baking soda and water first.Ok vise grips, hack saw, channel locks, dremel tool, whatever it takesYou will be buying new bolts and nuts to put on the terminals.Get rid of the acid, clean the area up. Rinse it down with water, dry it up. Protection is your choice. Baking soda is the cheapest way to keep the acid neutralized.Acid is what destroys.Now here is a test for everyone! Take your multimeter and put one probe on one pole, put the other prove on the plastic top and see how much voltage is seeping across in the acid on top of your battery.Voltage, and current flow where there is acid, and there is where the damage comes from.Clean batteries no voltage, and no current flow to do damage.Don't they call that elctro plating process? Yup it move the metal around .Oh yeah don't forget to clean the inside of the lead terminals!

I got some baking soda and water sitting on the terminals. The good hardware store is closed so I'll wait until tomorrow to get this nut off. I got all your suggestions down so I don't think I'll have problem. Thanks for all the help.Eugene

Now here is a test for everyone! Take your multimeter and put one probe on one pole, put the other prove on the plastic top and see how much voltage is seeping across in the acid on top of your battery. Voltage, and current flow where there is acid, and there is where the damage comes from. Clean batteries no voltage, and no current flow to do damage. Don't they call that elctro plating process? Yup it move the metal around . Oh yeah don't forget to clean the inside of the lead terminals!

Very valid point... I've lean on battery tops and touch a single terminal and the rest of my arm on the plastic and yea feel the tingle run through your arm from the current flow. Also like Elshadow is pointing out the batteries last much longer being clean because it not leaking current across the battery.

He is 120% correct, it is a constant drain on the batteries when they leak across from pole to pole or pole to ground.It's like a tire with a small leak, it will run out eventually if you don't stop itKeepem Clean. Again just baking soda, water and a small brush to clean it up, and next time it's much easier.

I just had to replace my neg. terminals on both batteries. what I did find weird was that the positive terminals were fine, and such. the negative one, however, had the bolts all but completely eaten away. no acid on the battery, it's nice and dry. but the terminals were slightly corroded. cleaning them off exposed the near non-existant nuts/bolts.. weirdness

Your right Rogan. Mine is exactly like that. Weird. Then I had more fun. Passenger side clamp won't budge. Tried to pry if off w/ straight screw driver and the whole post comes off. I thought I was strong but I didn't think I was that strong. That whole battery was toast. And while trying to get that post out of the clamp, I torn one of the ear off. That lead was soft. I decided to cut both clamps off and got one of those clamped on ends. It's just temporary so I could get the truck running. Going to a real auto parts to get some clamped for the I posts. Sodder, heat shrink and it should be good for a while.Eugene

Boiling water & someone-elses toothbrush LOL!!. The corrosion will disolve... then hose down the run off off your truck. I was brought up to grease the terminals but I've found the red & green treated felt washers actually do work. I have used them ever since. Sometimes I've had to resort to using a light hammer (& prayer) to free the terminals... the battery posts / terminals are tapered. Get it as clean as possible. Apply some penetrant oil to the battery/terminal joint. Gently tap the terminal in a rotational direction & then reverse. It will likely move & then can be freed with bif *ss pliers. Then use vise grips & wrench to unfasten the bolt. Or hacksaw through the center (open) side of the terminal... cut through the bolt & remove both halves. Replace the bolt. (On boats, I use to routinely replace with stainless.) Terminals are lead & can be stretched by repeated tightening. I've clearanced the open side allowing reuse of an otherwise ok cable. Hope this helps,Russ

Boiling water & someone-elses toothbrush LOL!!. The corrosion will disolve... then hose down the run off off your truck. I was brought up to grease the terminals but I've found the red & green treated felt washers actually do work. I have used them ever since. Sonetimes I've had to resort to using a light hammer (& prayer) to free the terminals... the battery posts / terminals are tapered. Get it as clean as possible. Apply some penetrant oil to the battery/terminal joint. Gently tap the terminal in a rotational direction & then reverse. It will likely move & then can be freed with bif *ss pliers. Then use vise grips & wrench to unfasten the bolt. Or hacksaw through the center (open) side of the terminal... cut through the bolt & remove both halves. Replace the bolt. (On boats, I use to routinely replace with stainless.) Terminals are lead & can be stretched by repeated tightening. I've clearanced the open side allowing reuse of an otherwise ok cable. Hope this helps, Russ

You're right on Russ, thats the way I do it with old tooth brushes and baking soda. The baking soda also works better than Tums for acid indigestion. Kerley

This post is just about done I use vinegar then rinse it off. This cuts the electrical corrosion real fast.

Bill