wszypszak

I just bought a 2008 C300 4matic Sport with 9800 miles on it, and I do not drive a lot either, being retired and in the process of building a new home. Since this is, or may be, the 4th winter on this car, what recommendations would anyone suggest as a replacement battery, trying to stay as close to factory original as possible? It is garage kept, and I keep a C tek trickle charge on it to offset the parasitic electrical loads, but battery replacement to me is normal maintenance. The OEM warranty runs out in July, so I am wondering and asking for insight and advice. All are welcome.

Carsy

From what I read on this site MB OEM batteries can last 8 years or more so I would replace it closer to this time.

The OEM batteries today are AGM ( Absorbed Glass Mat) type which have superior qualities to the wet lead acid & handle better the high electrical loads of the modern car.

You should buy the correct size ie Amp/Hour rating to suit the car.Diesels seem to have 70 A/H & petrol closer to 100A/H.

The AGM battery is more expensive initially than the standard but because it does the job properly & lasts longer it is good value.

I have a choice in Australia of buying the OEM Varta which is made in Germany or the cheaper USA manufactured Federal.

You should make sure your trickle charger is suited to the AGM battery & does not over charge & shorten its life.

Further information :- http://www.firststartbatteries.com.a...gmbattery.html

http://en.wikipedia.org/wiki/VRLA_battery

wszypszak

I feel I am in good shape because the c-tek is a fairly new invention, maybe 10 years old, that is a marvel of electrical engineering. I could explain what I know about it, but you would be happier going to their website or googling c-tek battery charger. Great item for the price. I do not have any affiliation with the company other than the fact that I bought one maybe 5 0r so years ago when it was now in the US market.

acr2001

Believe it or not, my 2012 C300 came with the old style Mercedes battery. It is "no maintenance" but appears to be completely identical to the older W203 battery, just has no ports to refill it. Not a glass mat battery. What gives?

Carsy

That is interesting. What is the brand ,was it made in Germany & where was your car built?

Mine is a Varta made in Germany, 70 amp/hr 760 AEN ( what ever that means, maybe cold cranking amps in German) & states "VRCA -Battery -Do Not Open"

They cost around A$800 from the dealer in Australia but less than half that from an independent battery seller.

Maybe MBUSA is cutting costs. You know that you purchase your cars at a great deal better price than we do here !!

Glyn M Ruck

All our cars here come with AGM batteries. That said the pre AGM OE 100Ah battery was bullet proof.

Carsy

One more thing to consider when buying a battery is to check its manufactured date.

Often they can be years old when sold which will shorten their life in your car.

Insist on a fresh battery & check the date stamp on top.

wszypszak

Very good point. when I bought my 3 year old Lexus RX, I but a Optima red top first thing. Never had a problem. My Mercedes, however, when it is time, I will stick with OEM.

Glyn M Ruck

+100000000000000000

acr2001

Maybe I'm confused...

Car was built in SA.
I'd take a photo but it's dark out.

The battery in my car looks something like the photo attached (the one on the right of course)
I figured the AGM battery would be considerably smaller.
Can someone post a photo of what the AGM looks like? Thanks!

wszypszak

I don't think I asked the question correctly. Here in the USA, if I want to keep my Merc all Merc, what brand of battery would I buy, or am I stuck buying one from a dealer, who may sell me a Sears Diehard in disguise- which, by the way, Consumer Reports likes Die Hards. Another question: Maintenance manual recommends brake fluid change every 3 year; under this guideline I am due, but with 10,100 miles on it, and superb brakes, is it necessary or just another traffic builder for the dealership' repair department? Any insight and advice is welcome, a always.

acr2001

If you want to keep it original, you will have to purchase a Mercedes battery. Either from the dealer or online.

The brake fluid change is a very good idea and should be done. If you look in your brake fluid reservoir you'll notice that the fluid does indeed change color as it ages. It absorbs moisture over its life. Without changing the fluid there is a risk of damage (clogging) of the ABS system. You also lose braking performance as air bubbles form in the lines. Plus if you were to overheat the brakes with the old water contaminated fluid, you risk it boiling which could lead to an accident.

Carsy

Hello Prof,

MB very likely source there batteries from a number of manufacturers dependant on where the car is built , where it is going ect. They will all be up to the same standard.

The clever thing to do is to source a replacement battery that is used by MB but from a shop other than the dealer. The price will be much reduced.

You will have to do some research in your local area to find the correct battery.You will then not be over a barrel when the time to replace comes. My battery is made in Germany by Varta.

Others may help with brand names.

I am surprised that your brake fluid interval is 3 years. Generally it is two.

Brake fluid needs changing on a time rather than mileage basis .This is because it is hydroscopic (absorbs water).

Having excess moisture in the brake system can greatly reduce performance producing vapour & a soft pedal. It can also damage/corrode the components.

I would change your brake fluid asap.

wszypszak

Thank you. Interstate is a very good name here and makes a very good battery for my car; as for the brake fluid, good advice well taken. Thank you.

Carsy

Take a look at the details written on the top of the battery. It should tell the story.

My 70 a/h AGM is 275x175 & 195 height.Battery is quite large & looks like the one you have posted.

The 100 a/h is larger again.

snarlingchicken

Reviving this somewhat old thread, but I had a question. My car is now only 3 or so years old (an 09 C350), and is currently at 18k miles. HOWEVER. Recently, my car's battery's been dying on me and just yesterday I had to call AAA as my car's battery died on me while at Costco. They checked the battery and found out of the 12v rating, it's at 9.5, and of the 700amps or so it should hold, it's holding less than 100. (numbers not exact). I can take a picture of the receipt showing the test results if needed. Anyone have any idea of what might be causing this? Only relevant mods to my car are a few lighting mods. T_T And now my car stutters to life (or doesn't start at all) when I try and start her up. Needing a new battery after just 18k miles seems pretty sad to me. Anyone care to chime in?

Edit: after reading, I'll have to go check how old the battery itself is.

wszypszak

I had a similar experience with a 2006 Lexus I owned. I hardly put any miles on it, and with the parasitic electric drains on it, one morning it was stone cold dead. Now I keep a C-Tek trickle charger 0n my C300 to keep the battery "full". I don't know if this applies to you, but at least it's a start. My 2004 Honda Pilot died suddenly- squirrels got up under the hood and snacked on some of the wires. Hope this gives you easy starting points, but I don't know about Mercedes enough to even suggest a remedy. It depends on temperature, proper connections, usage; I have always felt that the 4th winter is time for a new battery living here in The Peoples Republic of New Jersey.

Carsy

It is possible a battery will only last for 3 years depending on the conditions it has been under ie short trips, high ambient temps .

It also may have an internal fault.

A good idea to check terminal tightness & for corrosion.

Does it start well after a long run?.

You may have a earth leak draining it. Put the computer in engineering mode( dyno) to check the system voltage & amp load.

If you do have to purchase a new battery best to buy an Absorbed Glass Mat type.

It may be a good idea to have an auto electrician check the system & do a load test.

snarlingchicken

Gotta find out sometime tomorrow as my car is currently completely dead. 0 battery lol. Car won't even lock/unlock so I had to use the metal key inside the keyfob. I'll get a jump and take her to the dealership sometime tomorrow probably.

cdanfot

engine code P0128 checked battery voltage it is at 12.42 is this considered low?

C300Sport

Question for our battery experts:
My 2008, build date 9/07, has the original battery and I have not had any issues at all with it. I have a $50 MB gift card burning a hole in my pocket as it expires at the end of this month. I was thinking of buying the $165 battery at the dealership considering mine could give up the ghost at any time.
What is the longest you guys have heard of MB OEM batteries lasting? I would hate to replace a good battery with one that ends up only lasting 3-4 years...
Of course, it would be handy having a spare 12 volt power supply around the shop to test electronics with...

Carsy

Hello C 300,

I have seen on this site that the OEM battery can last over 10 years. I have a late 2007 built Varta battery which is still as strong as a bull.

I have done some planning & located a local supplier so can act quickly when the time comes. It will need an overnight courier. We also have a second car to go & pick it up!!

I think battery life will depend a lot on the conditions of use eg , whether the climate is hot or very cold , long or short trips , whether daily useage & if it was new when put in the car.

You could also have a free battery load test.

Maybe pour a cup of water into your pocket for another year ?.I am sure there is something ( fluids/filters/gaskets ) at the dealership to take your fancy .

Interested to hear when you decide.

JC

c300white

Yes - fluid will absorb moisture over time - not mileage - but you should be able to get dealer to measure moisture content (or you can get strips to do this at auto parts store). I had the fluid in my toyota for 8 years - and when I finally convinced dealer it test it - it was <1% water content - so did not need replacing (fluid still looked reasonably clear). If you are going to track car - maybe good preventative to replace to high BP DOT 4 every year. With motive (or similar) bleeder it is easy DIY. For normal use in non-humid climate - I would test every two years and see.

Carsy

My Benz maintenance schedule says to change brake fluid every 2 years. All the cars I have owned over a long period say the same or earlier. This timing is probably because it will protect the vehicle under all the conditions it is likely to face.

Industry uses planned maintenance schedules to maintain equipment before detrimental effects take place. I would rather do the simple & cheap procedure of flushing my brake fluid every 2 years rather than have borderline moisture levels in the fluid damaging components & giving less efficient braking.

JC

Carsy

C 300 Sport, What did you decide ? John