NickTH

My wife's 2015 E400 now approaching 4 yrs old.
Battery has performed flawlessly so far.
But wondering if it's prudent to be proactive & go ahead to replace both batteries now, or just wait until first signs of red light or sputtering starts...?
Don't want my wife to be stranded somewhere with battery issues...
Thanks,

kajtek1

The regenerative charging is battery killer and 4 years sounds like good time.
Still weakening battery will give you some warning. Common is slow cranking on cold morning.
Than I experienced that weak aux battery was taking long time before ECO stops would start to make their job.
Bottom line - IMHO the only good proactive is getting new car..
Everything else is a judgement call.

ghlkal

Good thought. If it were my car, I would wait for issues; but I do replace the battery in my wife's car to be proactive.

You live in a hot climate, and batteries don't last as long, so maybe it's time

mr e350

My 2011 E350 Sport 4M was built in March 2011 and I bought it new in October 2011. I now have 65,800 miles on it and I still have the original 2 batteries. When I took my car in for it’s 60 k annual service in October of 2018, I asked the service rep to check both batteries. Rep stated both were fine and that these batteries are good for 8/9 years if the car was used frequently which I do. It’s really your call if you want to replace both after 4 years. Good luck.

kajtek1

2011 doesn't have regenerative charging.
Whole different story.
In older MB we had batteries lasting 13 years, when I read reports about 17 years.
But again, new system when saves environment, kills the batteries

mr e350

I did not know that. Thanks for the info Kajtek1. Best regards

cetialpha5

The only way to tell if the battery is good is to get it load tested. If the results are good, you can just use the stock battery. If you want the battery to last, you could always try throwing it on a charger once in a while to get it fully charged up. The alternator doesn't always fully charge the battery and a fully charged battery will last longer than one that only gets partially charged up.

kajtek1

I have the testers Kent shows and it does take 2 different testers to fully test the batteries.
Sometimes battery will keep voltage, but will not deliver high amp, sometimes it it delivers high amp, but capacity is low and when it starts the engine, keeping the cabin lights for few minutes will run it low.
Pretty tricky business.

NickTH

Just checked with my local dealer.
They have Econo 20-month warranty for $110, Performance 40-month warr for $155, & Lifetime with Lifetime replacement (as long as you own the vehicle) for $210.
So seems like if we keep our E for another 4+ years, the Lifetime battery option makes sense.... ?

kajtek1

$110 sounds pretty cheap for MB battery, so what is it?
When you are taking your car to dealer, - you will qualify for roadside assistance who will replace battery at your home free of labor charge.
FCP sells MB brand batteries with lifetime replacement (I just bought smaller aux battery from them as it come only $15 more than from other guys with 24 months)
Than in last years PepBoys have the best deals on Bosch (96 months on flooded) or Champion batteries. Check their internet specials and current coupons.

Mud

https://mbworld.org/forums/e-class-w...-sourcing.html

Thanks to feedback here the Champion from Pep Boys was the best warranty and pricing.
I also wondered at the time about changing the original dash battery but decided to leave it - as mentioned the car will give an initial warning of low voltage.

spclagent7

My car battery died without warning yesterday morning. Other than eco stop/start being less active, there wasn’t any warning.

When I got in the car to go to work yesterday, the side mirrors barely folded out. When I tried to start the car, absolutely nothing. Dash, electronics, lights... Nothing. Good thing it happened at home in my garage.

I had just taken my car for dealer maintenance 3 weeks ago. At that time the battery apparently tested fine.

The good news is that the dealer determined that the battery failed early, and replaced at no charge under warranty. The battery came with car when new. The battery lasted 3.5 years.

oogurkan

I have 2015 w212, driving for 1 year; the ECO is not activating and I dont want it to be activated. I believe that my second battery is weak.

As I know that if you dont use start-stop system continuously then the battery life will increase.

I asked MB service to check the battery they said the voltage a little bit low, then they put on charge. But before that I dont have any problems (also till now). I suggest ask MB service or a good technician.

kajtek1

I replaced aux battery a month ago and the car was giving me warning about it being low.
Strange that with morning warning, after some drive the battery was still good and did ECO stops. New battery seem to make more stops, but system has too many variables to judge.
From what I read, ECO stops are done by aux battery, so they not suppose to affect main one.
I drive 1 car with ScanGauge and have volts on it, what shows charging voltage in the morning at 14.7V and I know this is shortening battery life.
For years I compare my MB to Ford trucks I have.
When older MB charging operate at 13.9V- batteries last for decade. Ford charging is at 14.5V and seldom batteries last more than 4 years.
New MB regenerative charging seem to make batteries lasting 3 years, when 4 is good result.

El Cid

Funny. M-B only warrants main batteries for two years or original warranty of 48 months. So, why would Service Rep. say they last 8-9 years? I had one die at 49 months and one die at 9 months.
Incidentally, unless you DIY it is hard to find a battery for M-B vehicles. Most auto parts places won't install them due to possible complications with M-B electronics. I tried several a year or so ago and none would install one.

Mud

Based on possibility of shorting out that front F32 fuseblock (among other things) from careless handling of leads the last thing I'd want messing with my car is the guy at an auto parts store.

Nothing against them, but most don't have knowledge of the secondary battery that leaves the electrical "live" even with primary battery disconnected.

kajtek1

I heard about Autozone replacing MB battery in MB.
Usually the job is given to trainee, meaning kid who was flipping burgers 2 days ago.
It happen that serviceman cross connected the battery and fried $5000 worth of computers.

DFWdude

I must be the only one to do this, but I have several cars. When a battery dies in one of them, there are additional choices to drive with until the battery can be replaced. In my experience, batteries go dead only in the garage overnight, so we haven't been stranded anywhere.

There is always a set of jumper cables in the trunk, just in case. But I've given more jumps to other people than I have to my own vehicle(s).

This way, a battery can be allowed to last 4 years, or up to 8 years before it needs to be replaced... the battery decides for me. Battery technology sometimes changes, so there's no need to buy a new battery ahead of its dead date.

In short, my wife has never been without a car due to a dead battery.

pamiboy

My car was getting closer to its 5 year mark when the battery suddenly died when I left it in the garage for a week or so without starting. Funny thing is, it couldn't be jump started, even by the tow truck guys (twice) which MB sent. They initially said something else might be wrong as well, but dealership replaced battery and told me all is fine.

El Cid

My experience with Auto Zone was that it was national company policy to NOT allow their employees to replace batteries in M-B's. If you search their site for batteries, they show ones for M-B, but there is a note: Professional installation required. I asked a very experienced manager what that meant and he said it means by company policy they cannot do it. I have used Auto Zone for decades in my other vehicles with no problems at all.

Crunch69

iTrader: (1)

Spend money on a quality battery

Most batteries are private label. Some battery facts, There are only 3 major automotive starting flooded battery manufacturers in the United States and four absorbed glass-mat (AGM) starting battery manufacturers in the United States.

The majority of Mercedes are equipped with a AGM battery.

Down here in the south the heat is hard on batteries a normal flooded battery only lasts 2 to 3 years max where the AGM lasts 4 to 5 years.

The AMG cost a bit more but

They are robust and do not leak or spill and they are relatively free from freezing damage.

Very little water loss

The internal resistance of the battery is very low so they charge faster and can take a heavy discharge without damage about 50%

Low discharge rate when stored for extended periods

Robuk

quote 2011 doesn't have regenerative charging.
Whole different story. quote.

It might have, if it has one of these on negative starter battery post it has regeneration.

Mr.Fly

This thread made me go recheck my main battery on my 2013 E550 with a SOLAR BA9 tester. I last checked it a year ago, and it tested out as marginal, so I continued using it since I seldom drive the car and it's almost always on a tender. This time, however, the SOLAR BA9 said it was "bad", giving only about 500 CCA versus the rated 800 CCA. Time for a new battery then!

After a bit of research, I decided to get a Champion AGM battery, in H8/Group49 size because a thread here on MBWorld said it will fit, even if Pepboys' website cross-referenced to a H7/Group94R size instead. The fact that Pepboys currently offer a 25% discount if you order or buy through the web, and are currently running a $40 rebate on this battery helped a bit in my decision-making. The total, after rebate, with taxes, came to under $120. For the data geeks, the SOLAR BA9 showed this battery as outputting >1000CCA, straight from Pepboys, even though it is rated at 900CCA.

Installation was pretty straight-forward. To extract the battery, after removing the cabin air diverter (?), I merely had to use a 13mm long extension socket for the bolt holding the battery down. I then hooked up my CTEK to maintain standby power to the car, and used the 10mm socket to loosen the terminals, obviously taking care not to arc anything since there was still applied power. I had to detach the overflow tube and plug from the old battery, and that was a bit fiddly. The original battery was a H7 Varta that was made in Germany. It was heavy, but not as heavy as the H8 Champion, also surprisingly made in Germany, that was purported to weigh 61 lb. It was a somewhat tight fit, but the new H8 battery went in fine once you get the wires out of the way. After buttoning everything up, I topped up the new battery with my CTEK; that took surprisingly long, given it was a new battery with a 4/19 date stamp. Oh well, I guess it was hungry.

I can't say my car started up quicker or more confidently. To be honest, the first startup after battery replacement felt and sounded the same as with the old battery – promptly and smartly. However, I now have confidence that I am less likely to be stranded with a suddenly dead battery. Plus it's another thing I don't have to worry about for quite a few years, especially as I'm planning a nice road trip with the car in summer.

PS: it may be interesting to note that the Varta and Champion appear identical, apart from their dimensional differences (H7 vs H8 sizes) – same molding shape, including cutouts at the base and other details of that nature. I'm guessing they were probably from the same factory.

cetialpha5

Varta and Champion are both JCI batteries so yeah, they could have come out of the same factory.

DFWdude

My experience is exactly the opposite...

I am genuinely confused whether OEM MB batteries today are flooded or AGM. One might think that MBs most consistantly popular model -- the E-Class -- would have the latest tech in batteries, but my experience so far in not proving out. My W212 was built on July 20, 2015. According to CarFax, the original battery was replaced under warranty by the previous owner in June 2017. That's just 23 months on that battery.

This 2017 battery was replaced again, under warranty, by the dealer for me on April 17, 2019 (just yesterday). That's 21 months life.

Accordingly, in my experience, these batteries struggle to make a mere 2 years between replacemets. If these are truly AGM battery technology, then please give me the old fashioned flooded batteries, instead. Those MB batteries last twice as long at least (5 years on average) in my old 2001 C320. IMO, I am NOT convinced that these higher tech batteries are any improvement at all. High tech is supposed to improve our lives, not require two-three steps backward.