For heavy-duty use such as off-roading, racing and power-hungry accessories like winches, plenty of owners swear by the Optima YellowTop D34/78. This pricey battery might be overkill for ordinary cars, though.
Deep well of power. The Optima YellowTop D34/78 combines the qualities of a starting battery and deep-cycle battery: You can run it nearly dry over and over, and it'll keep starting right back up. It powers pounding sound systems and extra lighting, and Optima even recommends its YellowTop batteries to run tractors and forklifts. It's also perfect for off-roading, experts say, because instead of fragile plates inside, the Optima battery has sturdy spiral tubes that stand up to constant vibration. The YellowTop D34/78 is one of the top-rated batteries in a leading test, shrugging off both freezing and sweltering temperatures.
Exceptionally long life for most owners. The Optima YellowTop can survive a decade or more of hard use, many owners say, but this opinion is not unanimous. Sajeev Mehta at TheTruthAboutCars.com had one Optima battery die after being in storage for six months, and another in his daily driver died right at the end of its three-year warranty.
Other car batteries offer better warranties. The DieHard Advanced Gold 50778 (Est. $165) and Kirkland Signature 12866 (Est. $85) both carry a three-year replacement warranty like the Optima, but add 100 months of prorated coverage after that.
Best if you need intense power. The expensive Optima car battery "isn't a good value for your daily driver," concludes Mehta at TheTruthAboutCars.com. "Non-street-legal toys and high-current applications are a different story." For example, the deep-cycle YellowTop is perfect for a limo TTAC overhauled, complete with power-sucking interior lighting and load-leveling suspension. Still, many owners wouldn't buy anything else. Note that though D34/78 is this battery's official model number, it may be marked or identified differently by different retailers. Regardless, the D34/78, 8014-045, 9014-045, 27991, D34-78, D34/78-950, YEL34/78, 989237, SC34DU, 3478DT and N9934/78YEL are all the same battery.
Editors here test 56 car batteries, including the Optima YellowTop 3478DT (D34/78). They rate each battery's life expectancy, cold-cranking amps (CCA) and reserve capacity, combining ratings for an overall score and picking the best batteries based on the results. They encourage subscribers to review the batteries, too.
Review: Optima Yellow Top 3478DT, Editors of ConsumerReports.org, April 2013
Pricey Optima car batteries aren't worth it for the average car, Sajeev Mehta says. However, they're perfect for off-roading, racing and other high-intensity uses. Mehta discusses the pros and cons of Optima RedTop and YellowTop batteries in minute detail.
Review: Product Review: Optima Batteries, Sajeev Mehta, Dec. 17, 2009
3. Cars Direct
CarsDirect.com recommends seven car battery brands, including Optima. They're expensive, Andrew Kaufman says, but they work in all conditions and last a long time.
Review: The Best Car Battery Brand to Use for Lasting Performance, Andrew Kaufman, Nov. 6, 2013
Easily one of the top-rated batteries here, the Optima YellowTop D34/78 averages 4.7 stars out of 5 in more than 170 reviews. Owners say that this Optima battery is powerful and long-lasting; price is the only real drawback.
Review: Optima Batteries YellowTop Dual-Purpose Battery, Group 34/78, 750 CCA, Contributors to AdvanceAutoParts.com, As of February 2014
The Optima YellowTop D34/78 gets mostly rave reviews here from owners who love the way it powers their off-road vehicles and power-hungry accessories. A few say the quality has dropped in recent years, though, and one warns that Amazon.com is not an authorized retailer so there's no warranty.
Review: Optima 8014-045-FFP YellowTop Group 34/78 Deep Cycle Battery, Contributors to Amazon.com, As of February 2014