Dear Car Talk Question: Plan to Address Battery Corrosion Doesn't Add Up

Hmm $1500 to clean battery terminals. $1.00 for a can of Coke, 15 minutes wait, and water to rinse. THAT is quite the hourly rate.

That dealer must have a really big boat!


This is clearly a situation that screams out, “Go to an independent mechanic”.

Or, for about $5, the OP could buy this product, and do it himself:

I think that it is a very good product.

1 Like

I had a battery that had corrosion buildup problem on the positive terminal. Iwas told tue post was not properly sealed on the battery. New battery and no problem. I dont recall if I lived with it until the battery died, or replaced the battery.

I’ve always been a fan of baking soda and water plus one of those terminal brushes. Some dielectric grease on the terminals at the end…I think the dealer flew past boat and entered yacht territory with that overcharge!


I’ve always used that combination–up until a few years ago–when I found that CRC spray at the auto parts store. Yes, it is more expensive than baking soda, but it is really convenient, as well as effective.

1 Like

That’s what I have always done. Heat the water with baking soda on the stove and pour over the terminal. Makes a mess on the garage floor though if you don’t catch it all.

There may be a less expensive way to repair the positive battery cable but I’ll bet the dealers parts catalog only offers a complete cable w/harness.

Many people have posted that it is common to see badly damaged battery cables, until now it seems, they only need to be cleaned.

Johnson Controls batteries sometimes develop a crack in the case next to the positive post and leak acid. Important to replace the battery before the damage occurs.



1 Like

There’s definitely something to be said for convenience.

don’t have that problem, no garage right now!

Same old thing , someone asking about a service price but does not list just what is going to be done . The price might not be out of line or it could be unnecessary work .


I think on repairs that a customer feels the amount is high. they should ask why and what is involved, so they understand. but most will not and will just complain about it afterwards.


I’m fond of a wire brush to remove battery corrosion. Works for me, and no chemicals to rinse off and hope that you got it all.

1 Like

A wire brush can leave behind microscopic bits of steel that will lead to further corrosion from dissimilar metal contact. Red ScotchBrite (Nylon scrub pads) are much better for cleaning the posts and clamps.

I also use baking soda and water. It is important to clean the top of the battery thoroughly after cleaning the posts. If you have removable caps for the cells, remove them and top off the cells with distilled water.

I have found those little anti corrosion discs to be very effective and keeping the corrosion from returning. I NEVER use grease to cover the terminals because it traps moisture against the terminals and leads to more corrosion. Typically I only have to clean the terminals and replace the discs about every 5 years.


The quote seems excessive, but one can’t tell without knowing the extent of the damage. Suggest a quote from a reputable independent shop, or several of them.

It is possible for battery acid to get into the cable itself where, when allowed sufficient time, capillary action can draw it the full length of the cable to connectors and components at the other end, causing additional damage. Inspect for this yourself or have a mechanic show you.

Checking terminal condition regularly and following the usual recommendations for cleaning battery and terminals and coating will prevent this. Keep the top of your battery free of acid, if acid returns soon, determine and correct the cause.

This and dozens of other things should be part of your routine inspection/preventative maintenance program (see your owners manual or get the list from a dealer). If you’ve been relying on a dealership or someone else for routine maintenance (and taking it in frequently enough), this shouldn’t have happened - be sure they’re truly doing everything on the list (example, are they attending to out of the way places like caliper sliders?).

Ken , Julie does not have this problem . She just posted what was letter to Ray’s newspaper column. And I doubt if the person who wrote the paper will even know what was discussed here.

Thanks, I missed the source - it looks like I need to read the fine print in the headers.

March 10 |

  • | - |

Ken , Julie does not have this problem . She just posted what was letter to Ray’s newspaper column. And I doubt if the person who wrote the paper will even know what was discussed here.

At any rate, for others, I have had to replace the plate that the battery sits in. Due I suppose for failure to clean everything off once a year. Only cost a couple dollars at the dealer but still a little work with rusted bolts. I think the new ones are plastic. So yeah depends on what they need to do but if the plate is gone enough to not hole the battery tight, it needs to be replaced.

And still a lot cheaper then $150.

1 Like