Just keeping folks up to date on things as I slowly try to solve the charging system riddle and battery related issues.

So I decided to replace the battery, I found a small amount of corrosion on the IBS negative battery terminal, so I went ahead and pulled the negative terminal and then decided to pull the battery which was a BMW replacement make by Exide.

Found out the replacement battery was about 4 years old and it was unclear if it was really an AGM battery. So I decided to get a battery from Advance Auto due to price and availability. I was considering getting a battery from the dealer, but after a lot of thought, I felt the Advance Auto battery had a 3 year Warranty vs the dealer battery of only 2 years. Plus the Advance Auto battery was about $50 cheaper than the dealer with online coupons.

Well this is where the fun kind of starts. Ordered the battery online from Advance Auto with pick up at my local store, as they did have it in stock.

Online specs looked pretty similar to what was in the vehicle, however, when I picked up the replacement battery I noticed the specs were different! I also noticed that the handle on the battery was a single larger handle rather than the typical 2 smaller handles.

So this is where it gets interesting.

The BMW brand replacement battery was an Exide battery, unclear if it was an AGM battery.

Specs on the BMW battery were:
Manufacturer - Exide
900 CCA
160 Reserve Capacity
90 Amp Hour
2 small flip up handles

Advance Auto online battery info
Manufacturer - Johnson Controls, Inc ?
900 CCA
1000 Cranking Amps @ 32F
160 Reserve Capacity
?? Amp Hour - figure not on battery or in online specs
2 small flip up handles

Advance Auto battery that was in stock
Manufacturer - Johnson Controls, Inc
850 CCA
1000 Cranking Amps @32F
180 Reserve Capacity
99 Amp hour - figure was not on battery, was finally provided this value directly from Johnson Controls.

So here is the dilemma, in order to Register/Program a new battery to the vehicle, the Amp Hour rating is required. I assume you can somewhat calculate the Amp Hour rating of the battery, however, I would also hope that the battery manufacturer would also batch test a number of new batteries to see if the calculated Amp Hour rating was accurate. The Amp Hour calculation can be found on the Internet and you typically multiple the Reserve Capacity by 0.4167. Well this did not look promising because even at a 180 Reserve Capacity the Amp Hour rating would have been 75 Amp Hours!! Not so good compared to what was in the vehicle. I have to assume that maybe the AGM batteries may have a higher Amp Hour conversion rate than standard Lead Acid batteries?? As you can see the Amp Hour rating of the new Advance Auto AutoCraft Platinum-AGM battery is 99 Amp Hours per Johnson Controls! This clearly is not a direct conversion using the 0.4167 value seen on the Internet.

After a long conversation with the Advance Auto folks about how the battery on their website was not the unit being sold in my local store, they needed to address this as well as get the Amp Hour rating on the web site under the specs as well as start to add the Amp Hour rating to the battery labels. This is because all the software to Register/Program a battery requires an Amp Hour value. Advance Auto Passed my questions on to Johnson Controls and someone from Johnson Controls contacted me.

After speaking with Johnson Controls it also appears that they have started to change the battery packaging and now are moving to a single handle case design for the European type of batteries. Additionally due to changing electrical demands in newer vehicles they are now more focused on Reserve Capacity and therefore due to some of the design changes they are giving up a slight bit of Cold Cranking Amps for more Reserve Capacity. With the increase in Reserve Capacity the Amp Hour ratings are also increasing.

So I now need to properly Register/Program my replacement 99 Amp Hour battery in my E70 because the battery that was removed was only rated at 90 Amp Hours.

Overall very happy with the replacement battery from Advance Auto, just be careful in your local area of you are looking for a replacement H8 battery, you pay close attention to the Amp Hour rating, if it is listed and the handle configuration. The newer, single handle design battery has the slightly lower CCV, but the higher Reserve Capacity and Amp Hour rating.

The next task is to see if BMW has a SIB (Service Information Bulletin) for the V8 E70 where there is NO indication of a no charge situation!

Hopefully I will be back with some answers on the lack of a no charging indication.

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2008 4.8i Black with Tabacco. Black Y-spoke wheels and shadowline trim.