dacia

My car's (2014 E350 gas) main battery seems to be dying after only 5 years. After a long drive the voltage is only about 12.1.
Morning voltage is 11.9V which drops down to about 10.2v during cranking.
The car starts just fine though.
So I am thinking of replacing it with Bosch L4 or L5 AGM.
The difference is the L4 is rated as 800 CCA and the 20 hour rate capacity (Ah): 80
while the L5 is 850 CCA and 20 hour rate capacity (Ah): 95.
Original battery's CCA is 800.

Size is almost the same, the L5 is about 4cm, an inch a half longer.
If it physically fits can I replace the original one with the higher CCA capacity battery?

Thanks.

kajtek1

Nothing wrong with putting bigger battery than factory one.
Some RVs have 4 or even 6 batteries charged by standard engine alternator. and the house batteries get deeply discharged.
Coming to battery life, W212 fall for the trend to use AGM batteries.
The AGM batteries were not design for passenger cars and maybe this is the reason, maybe just job ethics go down in latest years, but seem 5 years for them is good as most of W212 have batteries replaced before they reach 4 years.
I have flooded Bosch battery in my W211 that come with 96 month warranty and am tempted to put another one like it in my W212. Hard to beat $120 price at PepBoys.

Ungarisch

I went to a Group 49 battery, which is the largest that will physically fit within the battery tray in the front.

You really cant beat the Bosch AGM, even for $176. I bought mine in summer and at that time it was only $125 after the 25% online discount. Battery prices rise in the winter.
https://www.pepboys.com/bosch-premiu...product/838838

EDIT: I forgot to mention that our cars absolutely NEED an AGM battery to cope with the *****ty "smart" variable voltage alternators we have, because the car run off battery most of the time under normal driving conditions to save on fuel economy, and regular lead batteries don't continuous drain on them constantly.

cetialpha5

Just an FYI, the Bosch battery is an Excide. Pepboys also sells the Champion battery now which is a Johnson Controls. Varta was the oem for the car and they were a Johnson controls battery.

ygmn

world is pretty much down to 2 or 3 battery manufacturers for cars.

but they have a whole bunch of names on them

Ungarisch

This is very good info. While I'd prefer to go with Varta (Champion), I'm not sure that the latest Varta's are as good as the ones that came in MB's 10-15 years ago which were quite the endurance champions!

My w210's original factory Varta battery lasted from 2001 to 2012, I replaced it in 2012 with another MB original part battery (I think also Varta), and that lasted about 5 years, though my driving habits changed a lot since it then as it became a second "back-up" car that was rarely driven when we bought the W212.

My W212 on the other hand has had nothing but issues with the main battery, I shiatt you not I'm on the 6th or 7th battery on this car in under 8 years. It seems to destroy batteries every 9-15 months. The car originally came with a Varta which lasted 2 years, replaced with another MB original battery which lasted 1 year and once the warranty ran out I kept buying the Bosch AGM's and abusing the 48 month battery warranty on it as Pep Boys replaces them with no questions asked.

I'm not exactly sure why it's happening. I did both parasitic draw tests with an amp clamp which checked out fine, as well as Xentry battery sensor diagnostics which returned no issues with modules not going to sleep. I'm not going to say that new Varta and/or Bosch batteries are crap as it's obviously my car that is the issue.

I recently bought a CTEK trickle charger and been hooking the car up to it once every 2 weeks on the weekends, which seemed to have extend the life of this latest battery to a near record 16 months, but I should not be needing to trickle charge a car that is daily driven. I think this battery is on it's way out as well since after a 3 hour drive the battery read 12.2 volts right after shutting the car off.

kajtek1

Additional update about Bosch batteries at PepBoys,
I just bought another one for my W212. Chosen flooded regarles recommendations for AGM.
PepBoys have internet special for about $120, so you have to place internet order, entering W210 model with scheduled replacement at the shop. I than drove up there with old core in the trunk and picked up new battery saying I will install it in other car at home.
Brought it home and put my hi-tech Solar tester on it. The 1000 CA rated battery show 1260 amp. I am satisfy with performance and even more with 96 months warranty.
W212 has so-called "Smart charging" who suppose lower emissions and save fuel. That makes constant charging and draining the batteries what definitely shortens their lives.
Than AGM batteries don't seem to last as long as flooded, so maybe we do have 2 effects on those cars as I have not met W212 owner with battery older than 4 years.

zeemob

I'm still on my original battery. It's a 2012 with 64K miles right now. It was delivered on 09/2011.

Sunnyslope48

Yes, 12.2 volts is extremely low. Recently I had the dealer update the map file in my 2016 and they took one additional step and that was to 'adjust the voltage'. They didn't say exactly what that meant, or how they did that adjustment, but I take it to mean that the charging voltage upper limit was changed thru the computer. Might be something that could help your situation.

dacia

Update.
I bought a battery tester form Amazon and after hooking it up it showed that the battery's SOH (State of Health) was only 20%.
I had the battery on a charger all weekend long, yet the voltage was only about 12.2V (and after driving for about 45 min it was still the same).
When started the car the voltage dropped down to about 9.8V.
Tester says replace the battery. I also checked my wife's car's battery and that one was in perfect health, which it should be as it is only about two years old and the car is driven regularly.

So I ordered a Varta replacement battery, exactly the same as the original was as a bigger size would not physically fit on the battery tray, and it will arrive tomorrow.
The one in the car is 5 years and 5 months old, it has not been replaced yet, I have the service records.