Honest opinion from somebody who has sold interstate, optima and Advance auto brand... Interstate may last you 2 years before it takes a ****, Optimas are ok but not what they used to be, I wouldn't spend the money on it for a tow rig. For a lot less just get the high end parts store battery. A 34/78 series Autocraft titanium has the same or more CCA as optimas for less money and have a 3 year free replacement, 72 prorate warranty. KEEP YOUR RECEIPT! Make a copy since that heat transfer paper fades and keep it in tow piggy!
I've got an 02 Dodge Cummins I bought 1 year ago. It has a couple of Duralast batteries in it. This is the first time I've ever had a Duralast battery but so far I've been really pleased with them. Not sure if there is different levels of the Duralast but these have a yellow top.
I know I might be in the minority here but the last two Optima red tops I've had have been junk. They didn't last no time and I've got a buddy that hasn't had any luck out of them lately either.
The original Mopar batteries are pretty good but not sure about the replacements you can get from a dealership.
yeah i've heard the optima's are not what they used to be and for the price and having to buy 2 they were not on my 1st choice by far, i usually buy the biggest cranking amp battery walmart has for a gas burner but im wanting something a little better for the diesel
also i've noticed that interstate and diehard have 3 "grades" of their battery's
i have optima reds in my cummins, they come with 3 year replacement warranty. i take them to the local autozone every 2 1/2 years and get new ones for free. if we had an interstate dealer around here that is what i would have in it though.
Earlier this year I swapped out two Dekas that had been in my Cummins for over 5 years. Even then they were still going strong, the only reason I swapped them was because they started leaking and corroding around the posts. I went back with the exact same battery.