[RRRM8E]

I really can't fault the battery unless the Walmart ones are just cheap. My car sits for up to two weeks sometimes. I didn't drive it for 13 days recently and when I went to go somewhere, it did start but seemed 'weak' when it first cranked. Three days later, same thing. Three days after that, just click, click, click. Less than 15 minutes on the charger got me started and on my way to O'Reilly's.

That might not be the battery's fault.

 

[Bali]

My car sits for up to two weeks sometimes. I didn't drive it for 13 days recently

Put your battery on a maintainer when parked.

 

[Bali]

I think the convertibles can also use the H8 size.

I bought an H8 for my cab in error. Seems to me I discovered the error when I tried to install it. Any, back to Costco for H7.

H8 is too big for the vert. H7 fits.

 

[Effduration]

Need to buy an H7 (or size 94) AGM battery for wife's car today....Costco it is for $175 plus core..

It's 6 degrees outside and wife's original battery (AGM from factory) is 8 yrs old and starting to act up...

Walmart is usually my go-to for batteries, but none in my area had the Ever Start AGM

EDIT: I did buy a battery from Costco, unfortunately it had a 4/21 manufacture date...I don't like buying them that old...

 

[All2kool]

I think the convertibles can also use the H8 size.

Nope. The Cabriolet has as smaller battery compartment.

 

[The_Fixer]

Need to buy an H7 (or size 94) AGM battery for wife's car today....Costco it is for $175 plus core..

It's 6 degrees outside and wife's original battery (AGM from factory) is 8 yrs old and starting to act up...

Walmart is usually my go-to for batteries, but none in my area had the Ever Start AGM

8 years is a good run!

 

[RRRM8E]

Costco USA isnt as good a deal as Canada. But it is Saturday.
I wouldn’t get too fussed about AGM myself.

 

[All2kool]

That might not be the battery's fault.

Which is precisely why I said I couldn't really blame the battery.

Put your battery on a maintainer when parked.

Or just drive it once a week.

 

[Effduration]

I wouldnt get too fussed about AGM myself.

I would generally agree, but wife's 2014 MB came from the factory with AGM and has electronics and charging to support it. Further, the price difference between AGM and wet-cell ($50 or less) has declined somewhat since AGM's first came out.

This is the only AGM battery I own.

 

[RRRM8E]

I would generally agree, but wife's 2014 MB came from the factory with AGM and has electronics and charging to support it. Further, the price difference between AGM and wet-cell ($50 or less) has declined somewhat since AGM's first came out.

This is the only AGM battery I own.

I meant a regular battery will do just fine in a pinch, But yes, for under $50, I might do it.

 

[RRRM8E]

Which is precisely why I said I couldn't really blame the battery.

Or just drive it once a week.

I meant that it might not just be the age of the battery that is causing it to lose a charge. High on teh list of possible reasons, but not the only one.

 

[fanatichuman]

$150 at Walmart, $190 at O'Reilly's. But the O'Reilly's warranty is for a full three years and is not prorated.

Walmart is also 3 y free replacement warranty

 

[All2kool]

Walmart is also 3 y free replacement warranty

But they pro-rate the value of the battery you return based on the time left in your warranty. I had a month left - probably would have been given a $5 credit. Someone correct me if I'm wrong please.

 

[All2kool]

I meant that it might not just be the age of the battery that is causing it to lose a charge. High on teh list of possible reasons, but not the only one.

There is a mileage device in the car that draws a small current but that device has a battery in it as well. It's not been an issue until now - 3 years down the road and in the middle of winter. I probably could have charged the battery fully and been OK for a while but dropping $190 for a new battery wasn't going to break me.

 

[RRRM8E]

I replace batteries at five years. YMMV. I wouldn't trust an eight year old battery in winter so I totally agree with your move. My point was, there are other factors such as parasitic draw, weak alternator, faulty cables, too many short trips, to name a few, that will drain even a new battery.

 

[All2kool]

...weak alternator...

The battery was 35 months old albeit with low mileage. The Alternator has less than 1700 miles on it. We're in our coldest season here now with temps dipping below freezing last month. I don't drive very much so neglect is my biggest contributing factor to ageing a battery before its time. I may get in the habit of slapping the charger on it once a week for a few hours throughout winter. In the summer, I have a solar charger I can plug into the cigarette lighter port.

 

[RRRM8E]

I didnt realize you had hijacked the thread. OP had eight year old battery.

 

[RRRM8E]

Below freezing. Pshaw. -17F here overnight. My E91 was not interested in starting today. Battery chager hooked up. Risk of battery freezing if discharged.

 

[All2kool]

I didnt realize you had hijacked the thread. OP had eight year old battery.

I'm the OP and the battery was 35 months old.

 

[TLM]

Your other option for a budget solution is to buy a refurbished battery at Interstate. They are usually about $65. Comes with a 90 day warranty.

I’ve had several last at least 6-7 years in a bunch of different cars.