I buy my truck batteries at Walmart exclusively. Between the competitive prices and warranty (which I've used a few times) it's been the best deal.

 

I've used Everlast since replacing the original battery in the FX and in my "leave the FX in the garage cause it's shitty outside" Ford Taurus beatermobile. Walmart's got a smaller 4 something cca battery but it's the shitty 1 year warranty battery.