Quote Originally Posted by DamienOS
Quote Originally Posted by GERMANIKS
No need for an agm, the car might not even coded to take agm batteries. Registering the battery will not change that
From the top of my head the car can't even be coded for 95ah agm.
E60 m5 should be in 100-110ah, ideally 110. Do not compromise on the battery quality. I use to sell the Varta 110 for m5/535d etc but I am out of stock.

720amps you had before is a joke.
from doing a lot of reading pretty much everyone changing batterys in M5s replaces with the AGM variety so iam pretty confident it suits the M5 perfectly

glad to hear the 720 one thats in the car is not up to the job as it prob explains a few small issue iam having ( all electronic) .... now to track one down as they aint hugely common here

now ive narrowed it down to these two - not sure if the first one is in fact AGM tho - seems to be the highest spec where Amps and CCa are concerned

http://www.eurocarparts.com/ecp/c/BMW_M5_5.0_2006/p/car-parts/car-electrics-and-car-lighting/electrical/car-battery/?444779008&1&0bc5c57bb0231d87eb4dc037823601bb1ed19 56c&000020

http://www.eurocarparts.com/ecp/c/BMW_M5_5.0_2006/p/car-parts/car-electrics-and-car-lighting/electrical/car-battery/?444777008&1&c312eb2c48b42a8191676effd8d00a14a675a ac9&000020
First one is not agm. Second is. Your car will not run better with agm. Nice technology but you do not have to have it. Up to you and your budget.