After almost a two-year wait, I finally found a source for the BIG Optima battery. Summit Racing is finally selling this group 31 battery for $189.95. The good news is the battery is a drop in replacement for the stock group 27 batteries. The only small problem is getting the battery hold down bolts started, but with a little persuasion it worked. Last winter my ’98 stock batteries just barely were able to start the truck after a two day soak in -20*F temperatures. I am also sick of dousing these batteries with baking soda to keep the acid off the electrical add-ons connected to the terminals.
Here is a comparison of batteries.
The stock, group 27 battery installed by DC:
Length: 12 1/16”
Width: 6 13/16”
Height: 8 7/8”
CCA: 750
Reserve Capacity: 150 minutes
The Optima, group 31 battery:
Part number: D31A
Length: 12 13/16”
Width: 6 ½”
Height: 9 3/8”
CCA: 900
Reserve Capacity: 155 minutes
By the way, the cold cranking ampere (CCA) rating refers to the number of amperes a battery can support for 30 seconds at a temperature of 0°F until the battery voltage drops to 7.20 volts.
The reserve capacity of a battery is defined as the number of minutes that it can support a 25-ampere load at 80°F until its terminal voltage drops to 10.50 volts.
The big Optima battery
Linear Mode
