Replacement Battery

[My00Z8]

I've had my Z8 for 17 years, in air conditioned garage in FL. Always on trickle charger. The phone is not connected. I've had to replace the top of line Interstate batteries every two years. I need to replace again. Any suggestions and/or advice?Thanks

[boomster]

Replacement every two years seems excessive, especially if you keep it on a charger. You say you use a trickle charger, are you using a Battery Tender, which is actually a "float" charger? I replaced my battery a couple of years ago with an AutoCraft Gold 900 CCA, model 49H, which is still going strong. It cost about $125.00 at Advance Auto Parts after the core charge.

Bill

[mjunco1054]

I keep my Z8s on the BMW battery tender and use BMW batteries and typically I get many years out of the batteries typically 4-6 years. I do drive my cars at least once a month, and sometimes will leave them off the tender for a few days after I drive them. Not sure if that makes any difference, but I agree that a battery every two years is very unusual. My garage is also climate controlled. I am sure it is frustrating, so wish you the best in dealing with this.
Manuel Junco

[My00Z8]

It isn't a "tender" so that may be my problem.
Thanks

[Satch]

I have referred elsewhere to the Optima units. I own, like, four Battery Tenders, and now the two Optimas. I checked yesterday: both cars fully charged, and the Optima reads "MAINTAINING LARGE BATTERY." Life is good.

[Greensand121]

Satch..where did you hook up the Optime tender....direct to battery, lighter or in the hood?

[Satch]

I have wired connecting plugs (fused, of course) directly to the batteries in the Z8s; the plug wires are long enough to lie in the trunk with the floor panel in place. But before that, I just used the cigarette-lighter socket, which is live in the Z8, without any problems. I installed a similar plug lead under the hood of Party A's 335i because the cigarette socket was no longer live after the 2006 models.

[Greensand121]

Thank you Satch...i am going to get those!

[Satch]

Seems to be cheaper than when I bought my last one! https://www.amazon.com/Optima-Digita...rs+digital+400
Also available at the same price from Summit, I believe....

[boomster]

I've been using these for years on my non-daily driven cars and motorcycles with good results, and a little cheaper than the Optima unit. Typically get 5-7 years out of a battery. I have them connected directly to the battery in most cases, although I use the alligator clips for my car in Florida which I only connect when I leave at the end of the season.http://www.amazon.com/Battery-Tender...battery+tender

[Greensand121]

I needed 3 tenders...just bought two Optima 400's and one Deltran. Thanks for the tips!

[Satch]

As I've said before, I now own at least three Deltran (or BMW) Battery Tenders in addition to the Optimas. The Deltran has one LED that blinks red when nothing is happening, red when it's charging, and green when the battery is fully charged. It also has sharp metal edges, so when I use it on the Z4, I put a foam mouse pad beneath it on the top-down tonneau. If you just toss it in the passenger seat, those sharp edges can score the leather! (You don't want to know.) The Optima tells me the state of the battery charge, its current voltage, any amperage draw, and more important (to me, anyway), what exactly it's doing; in the images above, you'll see that it's in "float" mode, merely maintaining the battery charge. And although it has a wall mount, you can click it out for portability, and its plastic case is not likely to mess up leather or paint. But both or mine are mounted to be within range of the trunk batteries of Buffy and Nancy Drew.

[Satch]

I suppose I should buy a car cover embroidered NANCY....