I believe any = 12v battery that will fit in the box will work.

Starter batteries are not designed to be used as = auxillary batteries. Starter batteries are designed for short bursts of high amps. = Continuous draw down of a starter battery will greatly reduce its life = span. Deep Cycle Marine batteries are designed to be drawn down low hundreds = of times without harming them. The Optima sealed marine deep cycle seems to be = the best and the largest that will fit (barely) into the hole under the driver's = seat (See vanagon.com for details of fitting it). Finally, breathing sulfuric = acid (and other gases that come out of a battery) is harmful to your health. = The auxiliary battery compartment is not sealed or vented like the starter = battery compartment is (or is supposed to be). A sealed battery protects you and = your family's health.

-----Original = Message-----
From: Jen & Rog Johnson <rojen@CAPITAL.NET>
To: = vanagon@GERRY.VANAGON.COM = <vanagon@GERRY.VANAGON.COM&g= t;
Date: Saturday, January 23, 1999 12:34 PM
Subject: Aux = Battery 87 Westy

Recently the aux battery on my = '87 Westy Weekender fried (finally the answer to the sulfer smell - No: the = kid didn't stuff an egg salad sandwich into a heater channel). MY = INQUIRY: Must I replace this battery with the factory spec or can I install a = spare 12V battery I salvaged from my '86 Jetta? If these vehicles do = not call for the same size battery do I run a danger in performing this swap?