Ultimate Battery Guide, for future generations of FAQers

[eastsidebimmer]

I've been around these parts since 2005 and I've seen a lot of "What Battery?" posts: CD has chimed in multiple times recommending Dealer sourced 55AH or 66AH batteries, Others like Walmart's Group 26, many pros/cons on red top and a fair share of praise for Interstate and DEKA. Searching on the term "Battery" here on the FAQ has not been extremely helpful. I've been using a 50AH BMW branded battery 61-27-7-567-181 for about 4 years and after an 8 week period of storage with no battery tender and a 1600 electric clock, this battery is toast and will no longer take a charge.

If you've purchased a standard 2002 battery (front location) in the last few months/years and are happy with the results, please reply with the brand, size and where you purchased it. If you know of a useful old FAQ thread that I can revisit, please post it here too. I'm going to purchase new batteries for both of my cars and want to make a good choice. Thank you, -Ben

[roadhog0]

I have a Costco battery, I forget the fitment number but the only thing wrong with it is that the poles are on the fender side instead of engine side... (reversed)

[c.d.iesel]

me thinks your suffering from a draw rather than a 'poor' battery.

radio

clock

bad diode in the alternator - all will cause dead battery

[Napes]

I use Durolast Batteries from AutoZone. They are made in Mexico and the 60 mos. units usually last me about 72 mos. But, I live in a "warm" climate and if you're in a cold climate you may not get the same life out of them I do. Use 'em in both my '75 and my wife's '76. The P/N is worn off so I can't read any details. My records indicate this one's been in my car 4½ yrs. now. If I remember correctly they cost around $60.

Bob Napier

[eastsidebimmer]

me thinks your suffering from a draw rather than a 'poor' battery.

radio

clock

bad diode in the alternator - all will cause dead battery

Hi CD, my 1600 does have an electro-mechanical clock, I assume this is what ran the battery down after sitting all summer. It is just interesting that now it won't take a charge, either from the car or via battery charger.

[02again]

I think the rule of thumb with lead acid batteries is they will, on there own, lose 1% charge per day. Putting a little load on them and it's got to be less.

My 02 cents worth

[Mike Self]

a Group 26R. "R" means the posts are reversed--critical for use in an '02 with its original front battery position. You need to shim 'em slightly--a 10 inch length of 1x1 placed between the battery and the inner fender well will allow the battery holder to grip the battery's other side.

26R's are pretty commonly available at auto parts stores and Wal-Mart. I've used Wal-Mart because they are usually the cheapest, and seem to last 5-6 years--and my '02s hibernate about four months each year to avoid our Ohio road salt.

If you have a rear mounted battery, size is only determined by the area of the battery holder.

cheers

mike

[eurotrash]

Ben, my car came with a die hard battery from the PO. I have had it three years and it has performed so well (even having been relocated), that I can't get myself to replace it for a proper sealed unit for the trunk. (I know, I know..)

[Harv]

I too have had great results with Die-Hard batteries over the years. Also used Interstates too. I have an Optima (on a tender) in my 02. Bought that after the BMW battery I bought didn't fit in the TEP rear brace. I know there is a BMW battery that fits in there but the dealer was adement about that was the only BMW battery.

John

[ClayW]

Right now, I'm using a WestCo 12V31M battery (designed for a Miata). It works really well. 425 cold-cranking amps. It's 25lbs and measures 7.5"L X 5"W X 7"H. It's a drycell, so you can mount it anyway you want and it won't spill. It's mounted to on of Tom Rafalski's (02 Again) mounting brackets under the back seat. Great battery; never had a problem.

When I had a TEP brace in the trunk, I ran an Optima Redtop. The battery was great; never skipped a beat. I even let me car sit in storage for a year and the battery never went dead.

[HBChris]

A group 47 battery requires no shimming, it is the proper size and same as the BMW Exide 567 181 battery shown. Try the Interstate brand, also fits a coupe.

[JohnS]

I've had good luck with the Die Hard International series

#31247

Group 47

650 CCA

790 CA

[Chamonix72]

I am using this same battery and installation. It works great, and even when the car sits for a week or two, it always fires right up. I will be relocating it to the trunk when I put the E24 back seats in however. I like that it's an AGM construction, and can be mounted in any way you see fit.

Right now, I'm using a WestCo 12V31M battery (designed for a Miata). It works really well. 425 cold-cranking amps. It's 25lbs and measures 7.5"L X 5"W X 7"H. It's a drycell, so you can mount it anyway you want and it won't spill. It's mounted to on of Tom Rafalski's (02 Again) mounting brackets under the back seat. Great battery; never had a problem.

When I had a TEP brace in the trunk, I ran an Optima Redtop. The battery was great; never skipped a beat. I even let me car sit in storage for a year and the battery never went dead.

[02Les]

This Bosch battery was bought/installed in the Touring (1998?) prior to the car being shipped to the US in 2000. It was still going strong in 2009 when I relegated it to one of my project cars. It's still being used.

[jgerock]

As Mike Self said ^^

26R is a nice small battery.

I have been using Interstate Batteries for years in most of my vehicles.

Much smaller than the big, heavy Interstate Group 42 that came with the car.

By the way, Deka Batteries are made by a family-owned business (East Penn Mfg) in Lyon Station, PA. The also make batteries for other companies (Walmart, etc.). They are a good customer to me for all their injection molding needs.

http://www.dekabatteries.com/