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Positive battery terminal 'countersunk'?

I’ve posted two recent threads on the similar subject of my wife’s dead battery, getting a portable jumper and connecting the jumper leads.

I thought it again appropriate to post this condition separately.

In one of the prior 2 threads, a gentleman mentioned GM side mounted bolts. That caused me to remember what my wife said the AAA fellow said when he came out to jump her car. He said he couldn’t connect to the driver side battery (1 of 2) and had to go to the passenger side battery since the driver side positive terminal bolt was ‘countersunk’. I just checked her car and the guy was correct. I’ve never seen such a thing before.

Both batteries are new Interstates that were installed by the local mechanic not more than 2 months ago.

I’m attaching a screenshot.


I am amazed that AAA couldn’t jump start your car. They use a portable battery booster device with large clamps to fit around most terminals.

There must be a reason why GM designated the right side battery as the jump start location, must be a safer to stand on the right side of the truck and perhaps more clearance at that battery.

Sorry, I wasn’t clear. AAA jumped the passenger side second battery instead.

But I 1) don’t understand how you can ‘countersink’ the bolt–not looking at the other battery I thought there was a washer between the bolt head and the terminal female connection and, 2) It seems like a problem that needs fixing?

I’m about the farthest thing from a mechanic but in all my limited experience checking and jumping batteries over the years I’ve never seen such a condition at either terminal.

I’m sure there’s a GM mechanic on the forum who can resolve this thing for certain.

To have the battery cable bolts extended and exposed is a hazard, there should be caps on the positive cable ends to guard against beer cans and wrenches from coming in contact with them.

Makes sense and I’ll get caps for my wife once I resolve her sunk bolt head problem (assuming it is). I know my Silverado is capped. But that still doesn’t answer my 2 questions/problems regarding her ‘sunk’ bolt.

I wouldn’t be too concerned about the missing cap but safety is the reason that the bolts don’t stick out 3" for your jumper cables. Why do you need two jump start locations?

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I don’t know that I do. And if that’s the reason, then fine. But I called the GM dealer and they said for their batteries both batteries have their + bolts available.


i was tightening the bolt once and the portion inside the battery snapped off. nothing wrong with my bolt, the battery portion snapped off.

is it possible that the plastic housing is just covering the head of the bolt?

or perhaps the original bolt was stripped (happens a lot,) and some tech replaced it with a regular bolt (done it myself in a pinch. I think a 3/8ths bolt fits in a battery, then it is very hard to get a grip on it.)

or it could be just broken off. This is less likely, as I would think it would strip before it would snap the head off.

Striping/breaking the bolt sounds reasonable.

Here’s the problem. If I present the condition to the mechanic, the logical result would be to fix the connection.If that ‘fix’ entails a ‘do over’ (new battery), I’m not looking for either me or the mechanic to eat a battery. OTOH, it’s not right, if that was the case, not to fess up and tell the customer straight away, ‘I goofed, here’s the situation’.So if I do not know the answer ahead of time, I could very well end up with an (avoidable) bad situation.

You got the vehicle jumped and you have a new battery. Is this even worth this much worrying?

Is the passenger side battery more directly connected to the starter?

Re the counter-sinking of the post: I’ve never seen that before on any of my vehicle’s batteries. But none of them use the side mount posts either. The purpose seems like it must have something to do w/the side mounting. Or it is simply to prevent someone trying to jump start using that battery, as a different location is recommended by the manufacturer for safety and/or efficacy reasons. Or the manufacture doesn’t recommend jump starting at all, as it can damage sensitive electronics in the car sometimes, and they make the post like that to be idiot-proof, so it’s not possible to jump start.

Note to OP: The right side and the passenger side are the same side of the vehicle. The driver’s side is the left side of the vehicle.

@tester posted this on another thread, looks like the cat’s pajamas.

The OP’s photos above are a little blurry, but if the configuration is what it appears to be, it seems like the cable ass’y clamps around the counter-sunk post, rather than screwing into it. It appears from the photos above the post is solid and besides being countersunk in the middle doesn’t stick out much beyond the battery surface to improve clearances.

It is worth it (to me) not really worrying about but needing to ‘understand’ why something that ‘look’s and performs’ differently than OEM was done by a respected, local mechanic. I visited the local Car-quest (he and NAPA supply parts for the garages in town) auto parts store yesterday afternoon and described the condition. Charlie is a smart and decent sort and has bailed me out many times before (that’s why I buy my RF7 and MOA from him for example instead of saving a few bucks through Amazon).

He knew right off what had happened, knowing the mechanic without me giving the name. He said it’s not unusual for a truck my age for the OEM bolt, due to corrosion, to not be usable going forward with a new battery replacement. The mechanic doesn’t normally have all the different replacement bolts needed and since there was a second battery that could be jumped, he inserted an Allen head sort of flush bolt/screw that he had on hand.

Charlie said to drive her car over next, he’ll confirm and order the correct bolt. I asked about the gold plated bolt, he said sure, it wouldn’t corrode due to the gold. By the same token if you just painted a steel bold head afterward with some loose paint around the house or put Vaseline on it, same would serve the same function. Frankly, I think the gold bolt is sort of cool . I’ll make the decision ‘gold vs. painted’ on price. I might just get gold for her Burb (I think she’d then think I ‘really’ did something super great with the battery situation ). And given that he pointed out all the corrosion on my Silverado’s + terminal, I’ll just remove mine, clean, reinsert and paint or Vaseline.

Then I presume I should add a cap to both auto’s + bolt heads.

I also like following this stuff up to the bitter end since I’m in no rush, the folks are nice and I end up learning a bunch of stuff I hadn’t known before.

An example of which–I explained to Charlie the whole experience with Connie’s Burb from AAA to now. He said that once a battery has been drained (her case having had the door open in the garage all weekend), the car (I think he said alternator) is not designed to bring the charge all the way back to 100% just driving. That to do so I needed to put the trickle charger on the batteries overnight.


How would I know that this bolt is the correct length, etc for my 2000, Silverado with new Interstate batteries? Your referenced page shows a number of other side GM bolts? Just ask the fellow selling on the website providing the model number of her battery?