I'm curious to know if you had to keep power to the car when you disconnected that battery, to avoid losing the radio etc. I have an emergency battery assist thingy that I was thinking I could use to maintain power. I have visions of saving money on the batery and DIY, and losing it taking it to the dealer to reset all the lights and the radio code.

Great post and some good advice about allowing the electrics to boot before starting.

I'm amazed at how clean your car is underneath the trunk floor.

JB,
Not to worry on the "disconnect" deal; all here whom have done the batt.
swap, have seldom if ever, reported losing "stuff/settings." I'm an elec.
idiot and all my stuff came back on, inc. time, stations, etc. I wouldn't
give it a 2nd thought and using an interim source is not the deal, imo.

The undertrunk lid space was only opened once a year for the past 6 years,
to check the spare tire press. and make sure the batt was green eyed and
full. I really think my oem batt could have gone another year, but worth
the "do" on my schedule, not the batt's, lol! I see your X is an '00; I'd
do the new batt, if it were mine, especially in those YYZ winters.
GL,mD

The only settings I lost were the date and time. Otherwise everything else stayed... radio presets were all still there.

Tho the underneath storage wasn't filthy, it had alot of grit that I can easily vaccumm out.

Wow, your battery lasted 6 years??? The batt in the 330 lasted 5 years (was starting very slow during the summer months) and the batt in the X lasted around 4 (died while changing out the coolant and waterpump). I did luck out by picking up a batt from the dealer for $139.99 plus tax.

Dan

Careful now!
 

Make sure you're stopped when you turn the wheel. It was a little scary at 75 mph!

dont kid yourself, oem battery is the best, and if you drive a bmw you should be able to afford dealers price.

Now there is a good pump for that battery sale at the dlr...:rolleyes:
What is that opin based on? Who do you think makes BMW
batteries, BMW? No arm wrestle, but really disingenuous, imo.

Werker is also the manufacturer of BMW's replacement batteries. So how does buying them from the dealer make them "better"? :confused:

UC,
I knew that, too...I was jes'poking. :D
Urban myths and conventional "wisdom"
abound here, too. ;)
BR,mD

Yeah great write up, but does anyone know if batteries need topping up with distilled water and to what level?, it is mighty hot out here ALLLLL so worried it will all dry up...