I don't get too many parts from the dealer, but I wouldn't buy anything but a Mercedes battery. And never, EVER anything (ANYTHING!) from WalMart.

Jay

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On the road, currently:
'83 300D (German spec.) 168k mi. - - Wolfgang (tucked snugly away for the winter!)
'87 300D 375k mi. - finally went over to "The Dark Side"
'87 300TD 225k mi.
Cannondale 66cm CAAD5 w/Campy/Jamis Aurora
Hujsak Custom Fixie/Landshark Track Shark Custom/Ahearne Custom 29'er

Interstate makes their own batteries; they don't buy them from anywhere. Mercedes and BMW batteries are Interstate batteries (Mercedes and BMW don't make batteries); check with your dealer for proof. I have.

As for warranties and longevity, if a battery lasts 5 years, then you've done good. Often, when we run the proration on a battery, the prorated price exceeds the purchase price right at about the 4.5-5 year mark. When that happens, we just sell the battery at it's normal price. Yes, the 7 years warranty is a marketing ploy whose proration will actually cost you more than a new battery.

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- Brian


1989 500SEL Euro
1966 250SE Cabriolet
1958 BMW Isetta 600

Brian,
I suspect that it may be a well cared for battery, never run down too much, if it needed topping up only distilled water would be used, avoiding high speed on rough roads which minimizes shock to the battery (and the driver) may contribute to the battery's longer life. Starting with a quality battery with plenty of lead on the plates also helps.
There is only one lead acid battery manufacturer in Australia, their range is very limited, even most of the locally manufactured cars have imported batteries.
Best you people support your local industries !!

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Grumpy Old Diesel Owners Club group

I no longer question authority, I annoy authority. More effect, less effort....

1967 230-6 auto parts car. rust bucket.
1980 300D now parts car 800k miles
1984 300D 500k miles
1987 250td 160k miles English import
2001 jeep turbo diesel 130k miles
1998 jeep tdi ~ followed me home. Needs a turbo.
1968 Ford F750 truck. 6-354 diesel conversion.
Other toys ~J.D.,Cat & GM ~ mainly earth moving

Don't believe that's the situation. The required facilities to make batteries are extensive and that business is concentrated among two or three companies. Exide and Johnson Controls come to mind.

If you're of the opinion that Interstate makes "their own batteries".............where's the facility?

I'm sure you're correct. My diesels never go out unless they travel 30 miles or more...........and they start within five seconds independent of temperature.

Therefore, my situation is probably not considered typical of most.

My Dodge van, however, has a much more difficult life for the battery and it still lasts five years...........about the length of the warranty.

I'm still surprised that folks get less than four years out of a battery.

Then they must have made a mistake on their website:

http://www.batteries-faq.com/activekb/questions.php?questionid=51

Perhaps Interstate needs to improve its dealer training program!!!

Just goes to show you how good their marketing is...........they even fool their own dealer!!!

Thanks for the link.

Battery life varies in flooded-cell batteries, much more than simply the lead mass determines this.
The largest factor, regardless of the battery quality, is charging.

Regular lead-acid batteries have lead, and sulfuric-acid. When discharged, the lead turns to lead-sulfate and the acid to water (simplified). The lead-sulfate is not as stable mechanically, and will sluff off into the acid, drop to the bottom of the battery. This eventually changes the self-discharge rate and could lead to a shorted cell. Over-discharging makes it worse. If the battery is kept in a properly charged state, lead doesn't sluff off and the battery is less likely to be damaged by vibration and shock. Also, different methods of adding fiber reinforcement to the lead plates helps to keep it together when discharged.
The plates can be warped from overcharging/overheating, this too leads to shorted cells and changes the spacing between them causing different charge rates between cells.
Quality of lead, quantity of lead and the surface area of the lead is important. If the cells aren't perfectly matched one cell can charge faster or more completely than an adjaecent cell, causing a partially charged cell to not convert all of its sulfated surface to lead and slowly lose plate material permanently. It can also lead to overcharging the weaker cells, and over discharging the weaker cells, all shortening the life of the battery. Matched cells are extremely important in all multi-cell batteries.

Charging is again key. If not fully charged, or frequently partially discharged, you are using up charge cycles of the battery even though they're little ones. Things like a weak alternator and lots of accessories will cause this at stopliights.

Warranties are calculated, by marketing and product planners. The warranty is set by what is expected to sell the product, and when a warranty cost analysis is completed there is a determination made as to whether the quality will need to be improved (or degraded) to support the cost of warranty returns. In this calculation, you will find that just like lifetime muffler warranties, they're expected to be installed mostly in 2nd or 3rd owner cars where the owner won't own the car long enough to enjoy the full warranty period, or the car won't survive, and the few who do and use the warranty aren't significant enough to add costs to the warranty returns.
Further, the pro-rated is a tool to get you in for a new battery, and usually is exclusive of any sale prices or coupons, in most cases it's cheaper to find a battery on sale than to exercise your warranty (which often happens at the warranty-servicing store!) on a full-price battery.

I have a tendancy to buy my cars, and keep them for 10 years or more. Most of those cars I replace batteries at the 10 year mark because of age, and they're doing fine (original batteries). That goes from Ford, Volkswagen, Audi, Mercedes, even my Land Rover. Good maintenance keeps them in good condition. I've also run Autozone, Advance Auto, NAPA, Bosch, and Optima batteries with good service. I believe (without any data to support it) that the better batteries from each store is usually well made, better than their price leader, so it's what I buy. The Mercedes battery looks cool, and is likely a very good battery, but not convenient for me to buy and I consider the Optima red-top to be at least as good, fits, and available locally for about the same price (and looks at least as cool as the OE battery IMO).

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Gone to the dark side

- Jeff

I buy wal-mart batteries for one reason, price. I had to replace the batteries in my f350 diesel. $75ea at WM, $155ea at the interstate dealer who checked that alternator. If it were close I might consider the extra cost. But what can make a battery price gap that large?
The MB battery was $110 at the local tire store. But I was stuck needing it now, so I got it there. WM was again a lot less expensive.
I try and buy local when I can, but somethings make it too much to support the local guy, over the big chain.

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83 300SD Dark Silver Dark brown inside

.........marketing.........

That has been my experience with several NAPA batteries. When they complete their smoke and mirrors calculations, it usually turns out to be less expensive to buy a new battery outright than do a warranty exchange.
Things may have changed, but it used to be that a NAPA battery that failed halfway through its warranty period did not generate a credit equal to half the cost of the battery. Walmart, at least, uses straight line depreciation after the free replacement period expires.

Deep cycle batteries are boat batteries - they won't perform in an auto as well as a "starting" battery and their warranty is shorter. Our sailboat has two batteries, a start battery for starting the engine and a deep cycle battery for the house battery - cabin lights, stereo, bilge pump, etc.

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Houston, Texas
1984 300CD 235K miles, Elvira, one owner
1987 300TD 180K miles
1974 TR6 78K miles Sarah Jane, one owner
OBK #27

I just replaced the Duralast Gold battery in my Ford Explorer. It was rated at 750CCA but when the starter started cranking slowly I had it tested. It rated 230 CCA.

The battery had a 36 mo free replacement / 80 month warranty and I was 65 months into the warranty.

Originally the battery cost me $80.

Now the new Duralast Gold specified for my Explorer is rated at 850CCA, same warranty. New price is $109 but I got a $25 or so warranty credit.

Autozone never bats an eye when I need to use a battery warranty. I have done it two or three times now.

Once the battery started leaking on my Cavalier after about 2 years and they gave me a new one under the warranty.

Autozone is just so easy to work with and the warranty is a definite plus. Probably not the best battery in the world but with an Autozone on every corner they sure are convenient if you have any problems.

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1993 W124 300D 2.5L Turbo, OM602.962
2000 Chevrolet Cavalier, 2.4L DOHC
2002 Ford Explorer, 4.0L SOHC
2005 Toyota Prius, 1.5L

http://www.fuelly.com/sig-us/40601.png

That is precisely how the warranty game is intended to work. You paid $84 for a warranty exchange on an $80 battery and you are a happy Autozone repeat customer. Without the illusion of the warranty "benefit," you might have gone to Walmart and bought an equivalent battery for $75.

But I got 65 months of service out of it.

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1993 W124 300D 2.5L Turbo, OM602.962
2000 Chevrolet Cavalier, 2.4L DOHC
2002 Ford Explorer, 4.0L SOHC
2005 Toyota Prius, 1.5L

http://www.fuelly.com/sig-us/40601.png