Some top brand batteries will last 6 or 7 years but they do not have the strength at 6 years that they did brand new..Take it to a small battery shop and get it load tested..Or you could buy a jump starter pack to take with you..Sears makes reliable ones..
It doesn't matter what shape the rest of the truck is in if you have a weak battery. Your getting near the end of it's life, if you were staying local it would be no big deal to stretch it longer. But why take chances with your trip. We all know how quickly the weather can change out West. Change the battery for your own peace of mind. Enjoy your trip!
Original battery in the old girl's 2006 Colorado lasted 7 years from new. I figure if ya get 6 years out of an OEM battery, you're ahead of the game?
Then again, the battery in my hunting camp IH tractor wasn't new when I bought the tractor in 2005, has needed recharged several times due to "neglect" and is still going. Haven't had the charger on it since last spring.
When you understand that the batteries job is only to start the vehicle, then anything asked of it after that is just wearing it out prematurely.
20 years ago, we didn't have automatic starters, many of the key fob door openers, computers - On Star - that runs all the time.
Batteries today are a crap shoot, some might last 8 years while others only lasts about 5.
The Battery in the 09 Avalanche I drove went about a month ago.
I got about 6 years out of the battery in the '06 Pontiac Grand Prix GXP, but it wasn't driven all the time...
I think they would last a lot longer if I put them on a battery tender when the vehicle is not in use in the winter.
Actually, batteries fails more in the summer then in the winter..
When the mercury rises, a car battery's strength goes down.
Extreme heat, like 95° F outside combined with high temperatures under the hood, accelerates corrosion of car batteries.
Heat causes the water to evaporate out of battery fluid, breaking down the battery grids.
Weak batteries can struggle on for months, turning over the engine while it's easy to start and generate a charge. The real test comes when temperatures drop. A weakened battery has to overcome cold temperatures and a harder-to-crank engine because the cold thickened the engine's oil. The heat's attack lowered the battery's starting power, meaning someone's going to have to call for a jump-start and a replacement battery -- unless you get there first.