Please provide, the only grouop size listing I have is what Advance listed online, 90T5. Just sounds like an odd group size. NAPA lists the group size as 90 BCI, which also sounds odd.

 

The HHR battery is "odd" with the vent, so what you have found maybe correct. Don't know.

Johnson Controls does make good batteries - I've seen them in many commercial products.

 

Sorry Solman, Consumer Reports has no listings for the Group 90 batteries. I did physically check my HHR OEM and it is a 90-6yr. I suspect GM utilizes a new numbering system in a meager attempt to retain in-house replacement parts sales.

However, when I was in WalMart I checked their catalog, and using the number they indicated (I THINK it was 75) I checked their inventory. The battery is a true "maintenance free" and had a vent kit. It was a "first 3 year, free replacement" and had a little more CCA than the OEM....I think 700. The price was $77.00.

I was checking, because like you, I now have 5 years on my battery and wish to be prepared.

If anyone can confirm the "crossover" group numbers, I will post the CR testing results.

 

These batteries will become more and more common with the many cars now using them under the back seat. The Lacrosse, Malibu, Aura, Cruze etc all have the battery under the back seat. I am not sure but I think even the Camaro has it under the seat inside now too.

I did find this on the Optima web site in their fittment section.

2.Trunk/Interior Mounting – If your battery is mounted inside the passenger compartment or trunk (common in many European makes), the battery must be vented to the outside of the vehicle. OPTIMA group 27, 51, 78, 34C, and 31 batteries all have ports for connecting a vent hose.

One of these should work in a HHR. I will check into this.

 

Ok I just talked to my rep at Optima and they said this.

They do not have a listing for the HHR. But they do have some batteries with vent tube provisions. The way to tell if the Optima has this provision is to look for the two black circles on the top of the battery. If they are there there is no vent provision. If the top is solid with only the two terminals then it has the Vent provision.

You may need to change the hose depending on length of the one in the HHR in relation to the location of the Optima Vent.

I will do some more checking and see if we have a Red top that would work. I found a side terminal but not a top yet.

 

Yep, you're correct about this. I worked on this project about 12 years ago with the Aurora and then the CTS (they used BMW as a baseline study) GM discovered that this simple change provides durability and longevity to batteries.

I understand many changes will migrate. The cartridge oil filter, that we utilize on the HHR, as an example.

 

The other factors are less room under the hood in cars like the Malibu with the 3.6 and the fact the car will handle better with the weight in the rear and lower down. The HHR has it in the Spare well vs the quarter for a reason as it could have gone in the quarter panel even easier.

 

I find it interesting how old ideas come back. My 53 F100 had a cartridge oil filter. Often, owners would put a roll of toilet paper in the canister for a replacement.

 

Yes the Ford 239" Flathead was a good motor..

Our (former) '96 BMW Z-3 had a oil filter canister also, & since it was a mid-year model, the battery was in the trunk. Unlike the early 1996 Z-3 had battery still under the hood...

 

Ugh, I had forgotten about the toilet paper deal, just imagine shelling a main bearing because you used Charmin instead of Cottonelle.