Oda112

So, the first days of cold are here and my battery decided to end it's business with life today. Outside temps were around 60, I was driving around town running errands when the car decided not to start, leaving me stranded in a bank's parking lot. Luckily I was able to source some jumper cables and got it running again, enough to be able to get it back home. After doing some research on the internet, I found that I need a Group 49 battery, 90Ah, but the one currently in the car is a 80Ah one(OE MB) so it's the same you'd find in a V6. I thought the V8s needed a higher capacity battery, so I'm wondering if whoever replaced this one might have made a mistake. I peeled a sticker off the battery and found a another, smaller sticker with the date MAY 15 printed on it, which makes this whole thing even weirder. If it was replaced in 2015, then there's an issue with the car killing it's battery prematurely. There are no error codes present or any indication that the car has charging issues, so I'm ruling that out. Part number on the old battery is A0009822108 (12 V 80 Ah 800 A).
Anyway, I wanted to know if any of you replaced their battery on a V8 (m273) and if so, what type of battery did you put back in?

belarus27

I had one from walmart their everstart maxx lasted around a year and then started trippin a little , so after it died on me couple months ago i bought one from oreilys their superstar agm battery and so far so good. Came up to ~180

Oda112

Nice! I saw Autozone has a Duralast AGM for around 200, and it's rated at 90Ah as opposed to mine which is 80. After some more research I'm now thinking that maybe a trickle charger might revive it. I'm not driving that much (5000 miles for the past 8 months) and most of my driving consists of short trips ( 10 to 15 miles at most) and I think this might have prevented proper full charge of the battery. If that won't fix it, I'll have to get a new one.

KEY08

That exact Durolast from Autozone is what I put in my old 2010 E550. It weighs a ton! I paid $179, I think. Get a crane to install it. Haha!
Def try a trickle charger for awhile and see if you can get some more mileage out of your existing battery.

Oda112

Oh great! It figures that it would weigh allot and I need to replace it exactly when my helper is out of town Murphy's law at it's finest...
I'll get a CTEK and see if it will fix it for awhile. I'm still not certain about that May 15 sticker. Did you by any chance take a look under this sticker and had a date on it? I can't tell if it's the build date or the replace by date.

cetialpha5

Well 60 pounds isn't exactly a ton. I believe the group 49 is also the H8 battery. I believe you're right about the V6 battery, used to an H6 battery. Not sure about that date code. I believe MB has a 2 year warranty on parts so sometimes if the part is sitting on the shelf it may have been installed latter than 5/15. Not sure if that's a date code or a use by date. On my 2008, it was stamped on the battery terminal post with the date and month of manufacture. If the battery was installed by MB, it should be in the VMI. Hmm... I think labor is only one year though and they charge a lot to install a battery.

Anyway, Advance Auto has an H8 AGM battery for $192, use coupon code RJP225 for 25% off $25+ and you'd save $48 so it'd be $144. They also install it for free. Just keep an eye on them when they install it, make sure they disconnect the negative cable first and connect the negative last.

Oda112

There is a 12/15 posted on my negative terminal, if that's the manufacturing date, I'm in luck, it means it was installed after that date and I should be withing the 2 year warranty period since this was definitely a MB job. I'll have to give them a call on monday and ask nicely for a replacement. Do you think they'll try to deny replacing it because the job was done by the previous owner and I don't have any receipts on it?
Anyway, thanks for the info on the AA offer!

cetialpha5

Not sure how they treat stuff like that. It should be in the VMI, but then they'd have a record of who the owner was at the time. Also they'd probably test it to see if it's a bad battery. If it's just because you haven't driven it much, they'd probably just offer to charge it for you. You should just get the battery load tested at an auto parts store and if it fails the load test, then ask for a replacement. They usually that for free at most auto parts store. MB typically charges for everything.

Also I looked at the post on mine and it had a 45 07 on it which I think meant that it was made in the 45th week of 2007 which works out to about November which is about when my car was made. So that 12 might actually mean the 12th week so it'd be March instead of December. But who knows if they changed their numbering system. My W212 already has a replacement battery. I guess W211 batteries lasted a lot longer.

Oda112

Wow, 10 years, that's impressive! I think mine is too new to fail so I'm guessing the issue is my driving style. I need to take longer trips. Normally I would drive my truck around town for errands but sometimes I miss driving the merc, but I guess it doesn't like having to turn the engine 6 times in less than 30 minutes. I ordered a CTEK mus 4.3, I'll see if that brings it back to life.