Well...after needing to jump the X twice this winter...and not being able to use the REST feature during the cold days of Jan/Feb when doing short errands in fear that I'd come back to a dead X5...I bit the bullet and dug into the cargo area to replace the battery.
Interestingly...the battery wasn't as old as I thought. I guess a previous owner replaced it (with a BMW/Exide battery) somewhere between 6/2011 & 11/2012 when I purchased the X5...and I'm sure they paid a pretty penny for the BMW label on it...and it only lasted 3-4 years.
I usually go with Autozone's Duralast battery (which I actually replaced in my e38 this same weekend with a Duralast H8 DLG)...but Sam's Club had an East Penn's
Duracell 49 H8 battery for $114.87.
(The only reason the e38 got the Duralast H8 DLG battery is because the old battery purchased in Jan/2010 still had part of the pro-rated warranty left (the warranty back then was 2 yr free replacement with 5 yr pro-rated warranty which was good up to Jan/2017)...and Autozone priced matched the Duracell...so the e38's battery ended up only costing approx $85)
For approx $100 less than the BMW/Exide branded battery...along with having higher specs...I think the Duracell is a pretty good bargain. I guess the proof is in the pudding and we'll see if this battery has a longer life span than the expensive BMW branded battery. It definitely has higher specs:
BMW/Exide battery:
- RC (reserve capacity) = 160
- CA (cranking amps) = 720
- CCA (cold cranking amps) = 720
- AH (amp hour) = 90
Duracell 49 H8/East Penn battery (lead-acid):
- RC (reserve capacity) = 185 (see East Penn battery chart below)
- CA (cranking amps) = 1080
- CCA (cold cranking amps) = 900
- AH (amp hour) = 100 (see East Penn battery chart below)
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