Well well well...I have officially come upon the first problem with this car that's rendered it undriveable.

Two days ago, the car drove perfectly; started up normally, acted normal, and everything. I didn't drive it yesterday (except leaving the left side parking lights on; I park in the street in an area where sideswipes aren't uncommon; also, this hasn't affected anything before). Today, I went out to start the car and nothing. I heard what sounded like across between a buzz and a squeak, which turns out is coming from a black box on the driver's side inner fender almost at the very front of the car. With this, the brake and battery light appear to be on albeit very dimly, the glow plug light appears to not be lighting at all, and the car does absolutely nothing (except the fuel gauge going to 0) when I attempt to start it.

I pulled the battery and took it to Kragen, where they're able to charge and load-test a battery. After about 30 seconds on the charger, it came back with an error saying that the battery is inserviceable. Me being the ornery me I took the battery over to the boat I work on and hooked it up to a 10 amp charger. After almost an hour of the charger needle being pegged (I filled the cells all the way halfway into it, although they weren't that bad to begin with), I took a hydrometer to each cell...and with the charger still going, each one left the hydrometer float in the red, and two of them didn't even budge the float (actually, none of them really did). So, it looks like the battery's dead...

First, what batteries have you all had good luck with? I figure the higher cranking amps, the better, but what size/grouping is the battery supposed to be (the one that's there seemed to be a bit smaller than the battery tray)? Second, is this my real/only problem? What else should I take a look at? The warning light hasn't lit up except as a pre-start check, so I'm guessing the alternator's okay...

Thanks in advance! I assume I shouldn't go over to Albertson's and get a set of AA's OTOH if I do, maybe it's time to change the diesel spark plugs while I'm at it

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2001 VW Jetta TDI, 5 speed, daily driver
1991 Ford F-350, work in progress
1984 Ford F-250 4x4, 6.9l turbo diesel, 5 speed manual
Previous oilburners: 1980 IH Scout, 1984 E-350, 1985 M-B 300D, 1979 M-B 300SD, 1983 M-B 300D
Spark-free since 1999

Get the biggest battery that will fit on that tray! Look for something with AT LEAST 800 COLD cranking amps (CCA). I'm running an Exide (from Kragen) right now with 850 CCA. My old 300D had an Interstate battery that never failed me, so I'm lead to think that those are good too. I beleive Kragen warranties the Exide batteries for 84 months, which is nice.

Do you know what grouping sizes will fit in the tray?
I found a Group 49 825CCA Die-Hard battery from Sears for $100...although 825 seems a bit small (keep in mind that I'm used to having two 900CCA batteries wired together in my pickup )...

I'd like to keep it under $100 if possible, but will pay a bit more for a decent-quality battery with quite a bit of power.

sears die hard international.

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1984 300D Turbo - 231k....totalled 11/30/07 RIP

Happy to hear it 'cause that's exactly what I'm looking at. Unless I hear otherwise, I'm gonna plan on getting the aforementioned battery tomorrow afternoon. I just hope that buzzing/squeaking/whatnot was a symptom of the battery going, and not a separate problem...

Auto Zone has a size 49 for $60.00. I have one and it works fine.

Since there is an Auto ZOne almost everywhere, you can easily get warranty service. You don't even need the paperwork, they put it into their computer.

P E H

What kinda CCA's is the AutoZone battery putting out?

That's a thought, although I actually have a problem finding AutoZones around here...Kragen is more common, but I'm only really willing to buy oil and other fluids from them...the few engine parts I've gotten from them were prety low quality (explains the price), so I don't think I'd want to get a battery from them...

Actually, does Interstate have a battery that'll fit? I've got two of 'em in my truck, and am happy with them...if they've got a better price for an equivelant unit than Sears, I may go that way...

Used a no-name marine/deep cycle/ yacht battery that I got from my marina for the last 8 years on my 85' 300D. Just died two weeks ago. The car started, but barely! Replaced it with a Mercedes OEM battery; as they are one of the only few batteries that rate their power in AMP HOURS. So was my old battery, but it's no longer made.

Amps hours is more important than CCA for a battery!

Cold cranking amps refers to how much power a batter can theoretically produce when shorted (full load) at a given temperature; or in other words, how fast your battery can chemically react. Not really important unless you live in a really cold climate. Amp hours actually refers to the CAPACITY of the battery; ie: leaving your lights on for the day requires battery capacity (Amp hours), not theoretical maximum output (CCA).

Don't listen to the big deal that most autostores make about CCA unless you are going to short your battery with a breaker bar or something stupid like that, because welding is the only way you can ever use 700 or 1000amps (or closing your hood with the jumper-cabels on the battery). Last I checked, my starter and per-glow system used less than 200amps when starting, so i see no need for 1000 or more.

The Mercedes battery installed at my dealership cost me $109. They also gave me a free car wash, as they do whenever they do any work on any Mercedes. I went this way for the above reasons as well as Sears wanting $105 for their international. Don't like Autozone or Pepboys or other stores like that so, there. Can't give any specifics on it's longevity cause I just got it, but it deffinately starts better than I can remember; as well as having the Mercedes OEM white look.

As for the specifics on this battery for your comparison, the Mercedes OEM battery is:
-Lead Acid
-Servicable (can check, adjust, and add fluid) a must for me!
-100 amp hours (meaning it can supply a 100 amp load for 1 full hour, or a 20 amp load for 5 hours etc)
-450 CCA (had to translate this from German)
-2 year Mercedes unlimited warranty
-$109+tax installed (but this could vary based upon dealer, as mine included free install)

Just my $.02

If I could find another yacht battery like I had, I would have gone that way, but the ones they sell nowadays are junk compared to the old ones, and I couldn't find a fit.

ATLD

P.S> remember that Mercedes has unlimited roadside assistance for any Mercedes free of charge, no matter what battery you buy. This includes jumping your car, changing your flat, or giving you some fuel if you run out. You can contact Mercedes through 1-800-for-mercedes to recieve this service. They can do other more complicated things for you, but it isn't cheap as they charge you for those.

CCA and amp hours go pretty much hand in hand. The more of the one, the more of the other. But its the CCA that gets you started on a cold morning.

I had 2 MB batteries and they both failed prematurely. I wouldn't buy another.

The MB free road service is not unlimited. Ever read the part where the dealer can charge 1 1/2 times his normal shop rate?
Distance is limited also. So if you are in the middle of the dessert, 500 miles away from the nearest MB dealer, don't expect them to show up for free.

I never heard of Kragen so I would have a tough time getting warranty service form them, let alone buying a battery there. I live in the North East.

P E H

peh, you mean if we're out in the congo and the benz breaks down, they won't come to save us?
i read once that a rolls broke down in the desert and rolls went and retrieved the car .. put it into a container and shipped it back to england in order to repair it for the arab customer.
seriously though it seems to me that no other car company (besides rolls maybe) offers a roadside assistance program that covers the life of the car with any owner. it sure gives me some peace of mind and is especially comforting for the ladies. just my .02

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1984 300D Turbo - 231k....totalled 11/30/07 RIP

I have used the die hard international group 49 for at least 10 years. I have been very happy with the batteries, they seem to last a long time (I replace every 5 years).

They have never failed me (and I live in Chicago - cold winters). The car will start easily at -13C (of course, with good glow plugs and additive in the fuel).

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Jovan

'84 (11/83) 190D 2.2 5-Speed; Silver/Blue; Motor No. 00354, 402k mi (340+kmi mine)

'89 Porsche 911 Turbo Coupe; Black/Black; 53kmi
'05 BMW 530i 6-Speed; 302kmi
'19 Range Rover; 30kmi

Kragen, Checker, and Schuck's Auto Parts are one and the same; they just go by different names (3 separate companies that merged, I think). As far as I know, they're nationwide...just thought I'd let you know. I haven't seen a Kragen outside of California, but I saw a Checker in Las Vegas...

I think I'm gonna get the Die Hard battery on the way back from picking my girlfriend up from school this morning... Now let's just hope that that was the only problem.

Why pay more for advertising hype (Diehard). I've had Diehard batteries and they didn't impress me as being any better than other batteries that cost a lot less. I had one that exploded one time and Sears would not replace because I couldn't find the paperwork. Pep Boys was the same way: no pape, no batte. Auto Zone puts battery in their computer by your phone number and can throw away the papers.

I've been in Checkers on the west coast but Auto Zone seems to be all across the U.S. and more being built all the time.

P E H

As for the free roadside assistance, the services that I mentioned in my above post that i said were free, are free and unlimited (though if you run out of gas 10 times each day, they'd probally catch on). There is a service limit as to how far away from a dealer you can get the actual mercedes M320 to help out, but beyond that they contract with whoever is closer, AAA etc. As for the actual roadside repair, I'd charge more than 1.5x if I had to lug around all my tools with me to fix a car, but think; saves you the cost of a tow if it's relatively simple, or if your far from home. Though I still love the idea that you get those three simple things (and I should note that they are the most common car failures) free no mater what year the car is or how long you've owned it. Hell, if I had just bought a 67' MB I'd get the service. I guess it's just MB's way to keep less of their cars brokendown on the shoulders of the highways.

Anyway, as for CCA and amp hours going hand in hand, I can't agree. Just go to a marina and look at their selection, then find a Sears battery and call their manufacturer and compare the ratios of CCA to amp hours (not nearly the same). You'll find that the best batteries have a high rating of both, but as for cold starting current (CCA), unless you are going to need 1000 amps at 32 deg F, why bother when you can save money and get one with the engineering where it counts. Like I said before, you'd have to be welding with your battery to utilize that much current. Our starters are ~150 amps and the preglow is ~50amps =~200amps to start. Now, if you like starting your car with the headlights, defroster, foglights, radio lasting, airconditioner on high, horn, wipers, and brakelights on, then go for lots of CCA, but I never would. You have to remember, when you buy cheap batteries buy for amp hours, if you buy a $200 or $300, thenyou'll probally get both, so this is just my way of trying to help out those that ask for it.

Please, I don't mean to tell you to go and buy a battery with a rating of 5 CCA, no I just mean that the difference between a 500 and 1000 CCA battery cannot be realized by our cars in a realistic everyday situation. P.E. H., both these batteries will start your car on a cold day. As for the amp hours, that determines how much POWER you battery actually has. A battery with 1000 CCA and 10 amphours could even compare to a battery with 500 CCA and 100 amp hours. The later battery has TEN TIMES the POWER as the first.

If you think about it, the most expensive AA, AAA, C, or D batteries last the longest (amp hours). That is where build quality and engineering is required, not in a shorted load test. Personally, I think that CCA and CA is a marketing scheme used to distract consumers from the information that counts! I personally noticed that some of the highest rated CCA batteries are smaller compared to another typical lead acid, and that troubled me, as the amount or reactant usually coincides with the amount or reaction, not the rate of reaction. I don't mean to say that the MB OEM battery is the best either, I'm just trying to help instruct the warden in the physics of batteries and what I'd look for; as an engineer and scientist.

Just my $.02!

ATLD

ATLD,

As an engineer and scientist, you should know that ampere hours is not a power rating but a capacity rating. Power has to do with the time rate of energy usage I.E. watts, horsepower, BTU per hour ETC.

What I meant is that as far as car batteries go, if you get one with a high CCA, it will also have a high ampere hours rating and visa versa. I would suggest to always buy the best (and most expensive) battery available from the lowest priced supplier which is probably Walmart (no group 49) or Auto Zone.

P E H