I folks, I'm new to the forum and need some advice. While working on the car yesterday, I killed the battery by running accessories.

I live in a cold climate and want to buy a preminum replacement battery. Consumer Reports highly rates the DieHard Platinum. I am not sure if it is available for Cadillacs and when using their website search, I couldn't not find any for Group 34/78 (is this correct)? I tried calling and was on hold forever.

Any thoughts out there as to where to buy a new high performance battery at a decent price. Any suggestions, as to brand, etc. What's been your experience. Thanks, for you help.

Interstate makes an exact replacement for the 2008 and 2009 STS. It is their top of the line Megatron Plus series (MTP-H6). I don't know if it will fit an 06 or if they have one that will. Check their web page.

I stay away from the Diehard batteries myself as they do die hard. I had a bad experience with one when I had my Monte Carlo. It actually exploded on me. I would stick with Interstate or the manuafacturer's battery. If your battery was the original one, you got a lot of wear out it. Is your car still covered by the warranty? If it is, it could be covered.

I stay away from the Diehard batteries myself as they do die hard. I had a bad experience with one when I had my Monte Carlo. It actually exploded on me. I would stick with Interstate or the manuafacturer's battery. If your battery was the original one, you got a lot of wear out it. Is your car still covered by the warranty? If it is, it could be covered.

Sadly, it is not covered by any warranty.

Which battery/brand do you have?

I have to also say that a couple of mine failed and Cadillac replaced them via their roadside assistance. By the way, they were wonderful, I think it was probably the factory type. The Interstate batteries are great.

I just replaced mine. The Cadillac dealer had two different OEM Delco batteries for my 05 STS. One was $130 something and the other was $150 something. I got the better one and it cam with a 3 year 36,000 mile free replacement.

Optima Red top for me.. 1 month out of warranty my orig. let go. They timed it good. Autozone will install for you. Just be ready with the remote when the alarm goes off when the new battery is put in. I think I paid 140 or so.. I think it is one of the better batteries out there.

Porkfarm hit it on the head get a Optima Red Top battery 1000 CCA, I had to shop around a bit to find the right one, but I wanted the best, Porkfarm also hit it right on the head by be ready with the remote cause as soon as the cable hits the battery the alarm will sound off.
If you want the best buy Optima Red top,, anything else,,, just will cause you issues when say for instance the nav screen wont respond to touch, or your XM module doesnt show anymore, I had to keep resetting by disconnecting my battery for 5 mins and reconnecting, when you hit that starter such a drain happens to all the other systems that they get disorientated when you start your STS, pay the extra 50 bucks over the next 4 years it will pay off in knowing you bought the best

I just replaced mine. The Cadillac dealer had two different OEM Delco batteries for my 05 STS. One was $130 something and the other was $150 something. I got the better one and it cam with a 3 year 36,000 mile free replacement.

The 101-6YR, best Delco battery for the 05/06 carries a full 6yr pro rata warranty, beyond the 36/36 free repl.

It is still a DELCO. The Interstate Megatron-Plus carries an 85 (7 years +) month warranty with 30 months free replacement.

Here's an Idea...
Walk into any marina and ask them which battery they sell most of.
Any offshore boat I assure you will not be sporting a AC Delco battery.
I have an Optima blue top battery in my Lincoln I purchased new in 2004 still starts everyday, the Delco battery in both of my 2005 STS's have been replaced about a 1.5 years ago with Optima Red top batterys 1000CCA
Even Goober will tell ya at your local Auto Zone

As I found out last year with my wife's CTS, you cannot go to the local auto parts houses and buy an OTC battery for your CTS. The same holds true for the STS as I found out. The series of the battery is 101 for the STS. A dealer item only. They go for $178 and up depending on what dealer you talk to.

The parts houses will not sell you any sort of a replacement or try to fit something in of comperable quality saying "The incorrect battery was not made for that car and cannot warranty it." They are scared to even try.

I got in the yellow pages under "Batteries" and located a few businesses that stocked car batteries. I remember a place that my Dad used to buy Semi-truck batteries at. They looked it up in their books and came up with 101 as the replacement. They installed a battery of the same dimensions with the exception of the replacement battery being about 1/2 inch taller than GM DELCO coming out of the car. Had the same CCA as GM. Also the battery warehouse said, "It did not matter what car their battery went into, they would give the full warranty for it." A tight fit but no problems. Even the hold down mount matched up on the replacement battery and use the GM battery cover. Cost less than $70 with tax. It was the same on the CTS last year.
I checked to see what the number was on the replacement battery. It is a 78-72, side posts. Same dimensions as Delco, just 1/2 inch taller. It works fine.

I'm sure Interstate batteries would have a replacement you could install.

I would like to thank all off you for your thoughtful, quick replies. I believe I have enough info now to make an educated decision.
LMO

Welcome!