Date: Thu, 12 Oct 2000 11:03:09 -0400 From: "Dorffer, Rich" Subject: [uuc] RE: E36 M3 Battery Question... David stated > Hi guys..My car's battery just gave up on me today. I had to call my buddy to jump start it =(What is the "normal" life expectancy of the original battery? I haven't change mine since 95, so is it normal that my battery died just now? I tried to recharge it last week, and it seems it keep on losing power ever since (the battery that is, not the car =) ). So I'm thinking of changing my battery Can anybody please help me with the battery changing procedure? What type of battery I should get? what brand? Seeing as how I just did this and got tired of carrying around one of them their portable jump start booster things from KMart (Yep, from KMart, did not care for it really due mainly to the "lobster" claws which were somewhat clumsy/bulky and did not grab the metal contact areas too well....took it back and I am looking for something else), I went out and got myself a battery. Although Brett Anderson thought my battery had already been replaced once before based on it's appearance and certain criteria of an original stock battery, the prior owner and prior owner's BMW dealer had no record of changing the original battery during the first four years (13,000 miles) so it may or may not have been the original battery. Repost information (Can't remember who to thank for this as it was an excerpt I saved) The E36 BMW battery is a special group just for BMW...it is a BCI GROUP Number 92, 12 V 650 CCA, 75 Ah 340A DIN, 130RC. It is BMW P/N 61-21-8-353-651 (This part number has been superseded by BMW P/N 61-21-8-381-724), dealer list about $125. Douglas technicians in Winston-Salem, NC (home of Douglas Battery) affectionately call it a 48 1/2 group battery. Why? Well... A Douglas 49 battery will fit an M3, but it's about three inches longer than the stock battery. Getting the hold-down bracket to fit is a little tricky. A Douglas Group 48 will also fit, but it is smaller.. 625 CCA at zero degrees (800 CCA at 32). An Exide Group 49 has been reported to fit barely...Nascar Select P/N 49-84N 750 CCA. The Exide is about $80 at K-Mart Also try http://www.batteriesplus.com/product.html for a Group 49 battery. AC Delco also has a Group 49/93 battery with 650 CCA: http://www.acdelco.com/ And you might wonder, how did I jump from 90 range numbers to 40 range numbers? Well, a 48 interchanges with a 91, and 49 interchanges with 93. A Douglas 48/91 is 11 x 6 7/8" x 6 7/8". A 49/93 is 15 x 6 7/8" x 6 7/8"... bigger than the stock M3 battery, but an Exide 49 reportedly is not 15" long. FYI, the stock BMW battery dimensions are 7" W x 12 1/4" L at the very base lip, and 6 1/2" x 11 3/4" width/length overall. It is 7" high, but a slightly higher battery will fit (as well as slightly longer, but not 15" worth!) Anyway, I bought the Interstate MTPlus-91 which is a 72 month battery and has 700 CCA at zero degrees (http://www.interstatebatteryofdet.com/Automotive.html) Don't forget to have them give you a vent kit with the battery as it does not automatically come with it. It fits perfectly. Cost was something like $80 directly from the local Interstate distributor but other area places supplied by the distributor charge about $100. I also had to pay $2 for a vent tube kit as they were out of stock of the Interstate ones. Good luck and best regards, Rich