In 1999, after some research and finding that most small fleet vehicles in Alaska use the Optima red top, I bought one. Temperatures vary from -22 to +123 here, so I figured I'd have better luck with a battery which decline ratings in a year excede the capabilities of a typical starting battery within a month of little use. It lasted nine years for starting the truck and running a 100W HF rig daily, a lot of it while the engine is off. At roughly the nine-year point, the voltage would drop to around 10, causing my rig to reset when starting the truck. I bought a blue top to replace it, no problems yet.
I now have a new truck. I bought a left-side factory battery tray for a Diesel model and will run two Optima red-tops just for starting. The engine in this truck is nearly triple the size of the old one and the battery is almost 40% smaller, go figure. It really grunts trying to start in the single digits. For the radio equipment, I will have a third Optima red top in a steel box under the body of the truck. As for red, blue, yellow, tops, check the capacity and ratings, they are almost identical under all conditions, as per the Optima website. Kurt
