Interstate batteries! I believe the one you want is #MTP-93. 850 CCA/1065 MCA. Get it from the local distributor-not local dealer. Look in phone book. I just paid $88 for one for my W126. I've never seen a better conventional battery. Only bad thing is having a battery that does not say "Mercedes". If you show the car alot, get one from MB dealer. About $110 over the counter.

I may have found the reason why that battery went dead. It was an old battery anyway but something made it go bad a bit sooner.

I put the new battery on trickle charge last night. This morning, the charge was still on (it should turn off automatically). That seemed there was a little battery drain so I looked around.

Well, the two little lights on the bottom of the rear doors were on! The doors were shut but the lights were on. I played around a bit and found opening the hatch and closing it shut off these two little lights.

So it appeared these two little lights drained the old battery to a degree it tested bad.

BTW, it was 15 deg F this morning and the car started so much better with the new battery (it is not even fully charged yet).

Get Sears Diehard
Intersate batteries are no good

Can you be a little more specific as to why Insterstate (in your opinion) batteries are no good?

__________________
Current: '91 300TE 4MATIC 317k and climbing...
Former:
'81 300TD Wagon 168K "Tank"
'83 240D 216K 4spd manual "Da Bear" (aka best car ever)

"Never sweat the petty things...
and never pet the sweaty things."

I have had excellent luck with Marine rated, deep cycle yacht batteries. They are huge, but fit. Had one in my 300D for about six years with it NEVER going dead. That includes one time when my brother borrowed the car (his was being inspected) and left the headlights lights on for about 10 hours (work-day). He put them on in the morning and forgot to shut them off. Car doesn't buzz or have bright dash illumination, so he forgot.

Came back to the car at about 6pm that same day and saw his folly. Got in, shut the lights off, and poof, started right up! Amazing. And this was two years ago; when the battery was 4 years old!

Really makes people look astonished whenever I give em a jump.

Can't exactly read the brand off my battey anymore, but got it at the marina where my boat slip was (gate code is still the same). Imagine that you could do the same. Anyway, marine batteries are designed to have a continuous and powerful extended amperage draw. They can rebound from these "deep-cycles" very easily, and with a little driving. They are also less apt to be affected by cold, salt, or other environmental conditions. By the way; DON'T get a marine battery from Sears or another battery store: They aren't the same quality!

Hope this helps you decide.

Adam
ATLD

Yes, Bill. I paid $59 plus tax for the Autozone Group 49 battery.

Afraid I've had serial bad luck with Autozone batteries. Put a $59 one in my old Ford SHO; it was dead 8 months later. Got a free replacement, but sold the car about six months later. Also put a $59 battery in my old 123 300D. Dead after about a year and a half. Of course, I'd sold the car to a friend at that point... So it's anecdotal, but my experience with Autozone batteries is a 100% premature failure rate. Needless to say, I don't purchase batteries there anymore.

I have used sears ,interstate and autozone with no real difference in quality. The main difference in batteries/starting as far as problems is 1)the condition of your wiring, alternator starter.
2)The # of plates in the battery More is not better because there thinner and break with the vibration of the diesel engine.
Example: Some of the more expensive batterys "Gold series" have more plates better no more fragile yes.

The Yellow Top Deep Cycle Optima with 14.7 volts has given
good service for several years on the diesel powered Mercedes.
Certainly there is enuf excess power in the Deep Cycle Optima
to power all the car's accessories. Although expense, at about
$200., it should last for about twelve years or until the
car has no further economic value. Oh, it also is a gel battery
and never needs water.

replaced 'no name' batt in '01 with a sears die hard int'l
no problems yet...

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

two words - Sears International

__________________
Jim